The present disclosure generally relates to field of automobiles. Particularly, but not exclusively, the present disclosure relates to a BLDC motor of a fuel pump in vehicles. Further, embodiments of the present disclosure provide a stator lamina profile for a BLDC motor used in the fuel pump of the vehicles.
BACKGROUND
[2] The information in this section merely provides background information related to the present disclosure and may not constitute prior art(s).
[3] In a vehicle, fuel has to be supplied from a fuel tank or fuel reservoir to an engine of the vehicle. Most of the vehicles from ancient era use force of gravity to supply the fuel to a carburetor, which is fitted before the intake manifold of the engine. With improvement in technology, the fuel tanks have been positioned at different places based on design of the vehicle and as per the safety norms. The distant positioning of fuel tank from the engine requires a fuel pump to facilitate supply of fuel from the fuel tank to the carburetor or engine. With the advancement in technology, as carburetors were replaced by electronic fuel injections, mechanical fuel pumps were replaced by high pressure electric pumps. Electric pumps comprise of motors that generate sufficient pressure to extract the fuel from the fuel tank and push the fuel towards the engine of the vehicle through conduits.
[4] Motors being one of the uprising inventions of today's world are under constant development from its size or performance to its design and application. In the early development years of motors, there were only DC motors which uses brushes as a mean to commutate DC current to the windings and to rotate the rotor. Due to a direct contact between the brushes and the rotating rotor of the motor, a lot of friction is produced leading to increased losses, and with time these brushes used to get worn out, thus limiting the operational life of the motor and reducing its efficiency. AC motors were also developed

after DC motors but their operation was similar to DC motors thus faced the same losses issue.
[5] The vehicle manufacturers have tried and implemented different solutions to limit the loses due to friction in said motors. One such solution to subdue these losses, was to develop contactless motors known as Brushless DC and Brushless AC motors. The brushless motors having no direct contact with the rotor have overtook the brushed motors because of their high efficiency, long life, silent operation and their higher output to weight ratio in comparison with the brushed motors. The Brushless AC motors uses an expensive driver to run the motor in comparison to the Brushless DC motor, thus, the Brushless DC motors prevailed the market. The Brushless DC motors have replaced the convectional brushed motors in almost every application.
[6] Further, the convectional Brushless DC motor fuel pumps fitted in vehicles (for example: two wheelers) use a hydraulic unit with very fine clearances, which get clogged due to the impurities present in the fuel. Any impurity present in the fuel causes them to get clogged, thus reducing working life and overall efficiency of the BLDC motor as well as the hydraulic unit.
[7] In view of above, there is an immense need in the art to provide a solution to the Brushless DC motors of the fuel pumps to achieve the desired performance and longer working life by preventing the frictional losses and clogging of impurities in between the clearances.
SUMMARY OF THE DISCLOSURE
[8] The one or more shortcomings of the prior art are overcome by the stator assembly for an electric motor as claimed, and additional advantages are provided through the provision of the assembly as claimed in the present disclosure. Additional features and advantages are realized through the techniques of the present disclosure. Other

embodiments and aspects of the disclosure are described in detail herein and are considered a part of the claimed disclosure
[9] In one non-limiting embodiment of the present disclosure, a stator assembly for an electric motor is disclosed. The stator assembly includes a stator core and a plurality of coils. The stator core includes a plurality of circumferential slots extending in a vertical direction and a longitudinal slot extending along a longitudinal axis of the stator core. Each circumferential slot of the plurality of circumferential slots are separated by plurality of stator teeth. Each stator tooth of the plurality of stator teeth have optimized values of tooth width, tooth tang angle and tooth tip thickness. The plurality of coils are adapted to be received in each circumferential slot of the plurality of circumferential slots, such that energization of the plurality of coils facilitates operation of the electric motor.
[10] In an embodiment, the tooth width of each stator tooth is defined within a range of 1 - 1.5 mm.
[11] In an embodiment, the tooth tang angle of each stator tooth is defined within a range of 100°- 140°.
[12] In an embodiment, the tooth tip thickness of each stator tooth is defined within a range of 0.5-1 mm.
[13] In an embodiment, the stator core is defined having an outer diameter and an inner diameter, the outer diameter is defined within range of 27-28 mm and the inner diameter is defined within range of 10-11 mm.
[14] In an embodiment, each circumferential slot of the plurality of circumferential slots are defined having a slot depth and a slot opening width. The slot depth is defined within a range of 7-7.5 mm and the slot opening width is defined within a range of 1.5-2.0 mm.

[15] In an embodiment, the plurality of stator teeth are integrally formed with the stator core of the stator assembly.
[16] In another embodiment of the present disclosure, a fuel pump for a vehicle is disclosed. The fuel pump includes an electric motor and a hydraulic unit. The hydraulic unit is rotatably connected to the electric motor of the fuel pump. The electric motor comprises a rotor assembly and a stator assembly. The rotor assembly includes a shaft and a magnet. The stator assembly and the rotor assembly are enclosed within a housing. The magnet of the rotor assembly is rotatably received in the longitudinal slot of the stator core of the stator assembly, to facilitate rotation of the shaft and thereby to facilitate operation of a hydraulic unit coupled to the shaft of the rotor assembly.
[17] In an embodiment, the hydraulic unit includes an impeller housed inside the impeller housing, such that the impeller is rotatably connected to the shaft of the rotor assembly.
[18] In an embodiment, the housing comprises an inlet flange and an outlet flange. The inlet flange is disposed at a lower region of the housing and the outlet flange is disposed at an upper region of the housing.
[19] It is to be understood that the aspects and embodiments of the disclosure described above may be used in any combination with each other. Several of the aspects and embodiments may be combined to form a further embodiment of the disclosure.
[20] 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 by reference to the drawings and the following detailed description.
BRIEF DESCRIPTION OF ACCOMPANYING DRAWINGS

[21] The novel features and characteristics of the disclosure are set forth in the 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 description of an illustrative embodiment when read in conjunction with the accompanying drawings. One or more embodiments are now described, by way of example only, with reference to the accompanying drawings wherein like reference numerals represent like elements and in which:
[22] FIG. 1 illustrates a front view of a fuel pump, in accordance with an embodiment of the present disclosure;
[23] FIG. 2 illustrates an exploded view of the fuel pump of FIG. 1;
[24] FIG. 3 illustrates a sectional view of the fuel pump of FIG. 1;
[25] FIG. 4 illustrates a sectional view of a hydraulic unit of the fuel pump of FIG. 1;
[26] FIG. 5 illustrates a front view of a rotor assembly of a BLDC motor of the fuel pump of FIG. 1;
[27] FIG. 6 illustrates a perspective view of a stator assembly of the BLDC motor of the fuel pump of FIG. 1;
[28] FIG. 7 illustrates a top view of the stator assembly of FIG. 6; and
[29] FIG. 8 illustrates a top view of the stator assembly of FIG. 6, accommodated with a plurality of coils, in accordance with an embodiment of the present disclosure.
[30] Skilled artisans will appreciate that elements in the drawings are illustrated for simplicity and have not necessarily been drawn to scale. For example, the dimensions of

some of the elements in the drawings may be exaggerated relative to other elements to help to improve understanding of embodiments of the present invention.
DETAILED DESCRIPTION
[31] While the invention is susceptible to various modifications and alternative forms, specific embodiment thereof has been shown by way of example in the figures and will be described in detail below. It should be understood, however that it is not intended to limit the invention to the particular forms disclosed, but on the contrary, the invention is to cover all modifications, equivalents, and alternative falling within the spirit and the scope of the invention.
[32] Before describing detailed embodiments, it may be observed that the novelty and inventive step that are in accordance with the present disclosure resides in a stator assembly for an electric motor. Particularly, but not limited to the same, the present disclosure relates to the stator assembly for a Brushless Direct Current (hereinafter referred to as "BLDC") motor. It is to be noted that a person skilled in the art can be motivated from the present disclosure and modify the assembly or construction features of the respective components of said stator assembly. However, such modification should be construed within the scope of the present disclosure. Accordingly, the drawings are showing only those specific details that are pertinent to understanding the embodiments of the present disclosure so as not to obscure the disclosure with details that will be readily apparent to those of ordinary skill in the art having benefit of the description herein.
[33] In the present disclosure, the term "exemplary" is used herein to mean "serving as an example, instance, or illustration." Any embodiment or implementation of the present subject matter described herein as "exemplary" is not necessarily to be construed as preferred or advantageous over other embodiments.
[34] The terms "comprises", "comprising", or any other variations thereof, are intended to cover a non-exclusive inclusion, such that a 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 setup or device. In other words, one or more elements in a system or apparatus proceeded by "comprises... a" does not, without more constraints, preclude the existence of other elements or additional elements in the system or apparatus.
[35] The present disclosure relates to a stator assembly for an electric motor, preferably a BLDC motor, but not limited to the same. The electric motor is configured to drive a hydraulic unit of a fuel pump of a vehicle. The fuel pump is fitted with the BLDC motor to facilitate flow of fuel from a fuel tank to an engine of the vehicle. The fuel pump are employed in vehicles having engine as a power generating unit. The vehicles may include - two wheeler vehicles for example - motorcycles, scooters; four wheeler vehicles, trucks, commercial vehicles and likewise. The BLDC motor comprises a stator assembly, a rotor assembly and a plurality of coils of conductive wires wound inside a stator core of the stator assembly. The BLDC motor generates pressure to allow flow of fuel stored in the fuel tank to an intake manifold of the engine of the vehicle. The BLDC motor may also be employed in other applications, for example - BLDC motor may be utilized for allowing flow of any fluid from one storage space to the other.
[36] The stator assembly includes a stator core, such that the stator core is defined with a plurality of circumferential slots extending in a vertical direction and a longitudinal slot extending along a longitudinal axis of the stator core. Each circumferential slot of the plurality of circumferential slots are separated by plurality of teeth. Each tooth of the plurality of teeth have optimized values of tooth width, tooth tang angle and tooth tip thickness. The plurality of coils are adapted to be received in each circumferential slot of the plurality of circumferential slots, such that energization of each coil of the plurality of coils facilitate operation of the electric motor, preferably BLDC motor. The stator core is designed to enable the BLDC motor to operate at the high specified operational torque and low RPM in comparison to the motors of the same classification.

[37] The rotor assembly of the BLDC motor includes a shaft and a magnet. The magnet is mounted on an outer surface of the shaft. The magnet and the shaft may be defined to have a unitary structure. The shaft is adapted to be received in the longitudinal slot of the stator core. In an exemplary embodiment, the magnet of the rotor assembly is entirely received within the longitudinal slot of the stator core of the stator assembly. The energization of the plurality of coils received in the plurality of circumferential slots of the stator core generates a magnetic flux in the presence of the magnet in the longitudinal slot. The magnetic flux generated is configured to rotate the shaft of the rotor assembly and thereby facilitates operation of the electric motor or the BLDC motor.
[38] The BLDC motor is configured to operate a hydraulic unit of a fuel pump of the vehicle. The hydraulic unit includes an impeller housed inside an impeller housing. The impeller is rotatably connected to the shaft of the rotor assembly such that rotation of the shaft drives the impeller of the hydraulic unit. The rotation of the impeller at high rpms (Revolutions per minute) generates a suction force at an inlet end of the BLDC motor to facilitate flow of the fuel from the fuel tank to the intake manifold of the engine. The optimized values of tooth width, tooth tang angle and tooth tip thickness facilitate proper flux distribution to the shaft, to rotate the shaft at the rated RPM with the required torque to achieve the desired flow of fuel at the available current range.
[39] The stator core is designed for operating at high torque, low RPM and is highly spacious for accommodating higher insulating wire fill factors and is easy to manufacture. The stator core has space to accommodate the high number of coils turns required to generate the required flux. The stator core has optimized cross-sectional area to avoid high flux density regions and to perform at high efficiency. The stator core is designed with precise dimensions to perform at higher efficiency and higher torque values with a considerably small magnet mounted on the shaft of the rotor assembly.
[40] In an embodiment of the present disclosure, the heavier hydraulic unit is coupled to the BLDC motor in order to provide more clearance between the components. The clearance between the components is to be considered efficiently in order to prevent

clogging of impurities present in the fuel. The heavy hydraulic unit is provided with greater clearance so that the clogging of impurities in between the components do not takes place and which in turn increases the working life of the components. The heavier hydraulic unit requires bigger BLDC motor to generate sufficient torque at a pre-defined or conventional charge/current flow conditions to govern operation of the hydraulic unit. The BLDC motor in accordance with the present disclosure is having larger shape and size to accommodate the stator assembly.
[41] Reference will now be made to the exemplary embodiments of the disclosure, as illustrated in the accompanying drawings. Wherever possible, same numerals will be used to refer to the same or like parts. Embodiments of the disclosure are described in the following paragraphs with reference to FIGS. 1 to 8. In FIGS. 1 to 8, the same element or elements which have same functions are indicated by the same reference signs.
[42] Accordingly, the present disclosure provides a fuel pump (100) of a vehicle (not shown in FIG.s), preferably two wheelers. The fuel pump (100) is configured to fluidly connect a fuel tank with an engine of the vehicle, more preferably the fuel pump (100) is configured to fluidly connect the fuel tank with an intake manifold of the engine. The fuel pump (100) is mounted on the fuel tank of the vehicle or in a proximity to the fuel tank of the vehicle. Referring to FIGS. 1-3, the fuel pump (100) includes an electric motor (300) and a hydraulic unit (40). The hydraulic unit (40) is rotatably connected to the electric motor (300) of the fuel pump (100). The electric motor (300) is defined as a Brushless Direct Current (hereinafter may be referred to as "BLDC") motor, configured to operate the hydraulic unit (40) of the fuel pump (100). According to an exemplary embodiment of the present disclosure, the electric motor (300) hereinafter may also be defined as a BLDC motor to facilitate operation of the hydraulic unit (40). The BLDC motor is defined as a an electric motor which operates based on the magnetic flux created by the current passing through the plurality of coils in present of a permanent magnet. The operation of the hydraulic unit (40) facilitates flow of the fuel from the fuel storage tank to the intake manifold of the engine.

[43] The fuel pump (100) includes a plurality of terminals (101) located at one end and a mounting rod (102) located at another end of the fuel pump (100), as shown in FIG. 1. The mounting rod (102) to connect a filter assembly (not shown in FIGS.) with the fuel pump (100) of the vehicle. The plurality of terminals (101) are configured to electrically connect the BLDC motor (300) with a driver (not shown in FIG.s) of the fuel pump (100). The operation of the fuel pump (100) is governed by a flow of direct current (DC) stored in a battery to the driver and then to the BLDC motor (300) through the plurality of terminals (101). The fuel pump (100) is connected to the driver to vary the current passing through the fuel pump (100) in order to vary rpm (revolutions per minute) of the BLDC motor (300).
[44] The fuel pump (100) comprises a housing (30) adapted to enclose the electric motor (300) and the hydraulic unit (40). The housing (30) comprises an inlet flange (31) and an outlet flange (32), such that the inlet flange (31) is disposed at a lower region of the housing (30) and the outlet flange (32) is disposed at an upper region of the housing (30), as shown in FIG. 2. The inlet flange (31) is defined having an inlet port (31a) and the outlet flange is defined having an outlet port (32a). The outlet port (32a) is adapted to receive a non¬return valve (103) of the fuel pump (100). The non-return valve (103) may comprise of a longitudinal rod adapted to receive a coil spring. The non-return valve (103) is configured to prevent back flow of the fuel from the intake manifold of the engine to the fuel storage tank of the vehicle. Alternatively, conventional non-return valves may be utilized to prevent back flow of the fuel from the intake manifold of the engine to the fuel storage tank of the vehicle. The fuel pump (100) further comprises a bush (104) to connect the BLDC motor (300) with the outlet flange (32) of the housing (30).
[45] The electric motor (300), more preferably the BLDC motor includes a rotor assembly (10) and a stator assembly (200). The rotor assembly (10) includes a shaft (11) and a magnet (12), as shown in FIG. 5. The magnet (12) is mounted on an outer surface of the shaft (11) of the rotor assembly (10). The rotor assembly (10) and the stator assembly (200) are enclosed within the housing (30) and is sealed by the inlet flange (31) and the outlet flange (32) of the housing (30). The housing (30), the inlet flange (31) and the outlet

flange (32) are provided to prevent entrance of any foreign particles for example - dust particles, moisture and likewise into the electric motor (300) or the hydraulic unit (40). The electric motor (300) includes an upper bobbin unit (51) and a lower bobbin unit (52). The upper bobbin unit (51) is adapted to receive the plurality of terminals (101) and the bush (104) of the fuel pump (100). The upper bobbin unit (51) and the lower bobbin unit (52) are manufactured from an insulating material. The upper bobbin unit (51) is configured to accommodate the plurality of terminals (101).
[46] Referring to FIGS. 2-8, the stator assembly (200) comprises a stator core (20) and a plurality of coils (24). The stator core (20) is defined having a cylindrical shaped structure, but not limited to the same. The stator core (20) is configured to receive the upper bobbin unit (51) and the lower bobbin unit (52). The upper bobbin unit (51) is received till midway of the stator core (20) from top portion of the stator core (20) and the lower bobbin unit (52) is received till midway of the stator core (20) from bottom portion of the stator core (20). The stator core (20) is defined having a plurality of circumferential slots (21) extending in a vertical direction and a longitudinal slot (22) extending along a longitudinal axis (X-X) of the stator core (20), as shown in FIG. 6. The longitudinal axis (X-X) may be defined as an axis passing through center of the stator core (20) of the stator assembly (200). The magnet (12) of the rotor assembly (10) is rotatably received in the longitudinal slot (22) of the stator core (20) of the stator assembly (200), to facilitate rotation of the shaft (11) and thereby to facilitate operation of the hydraulic unit (40) coupled to the shaft (11) of the rotor assembly (10). Each circumferential slot of the plurality of circumferential slots (21) are separated by plurality of stator teeth (23). Each stator tooth of the plurality of stator teeth (23) have optimized values of tooth width (tw), tooth tang angle (ta) and tooth tip thickness (tb). The plurality of coils (4) are adapted to be received in each circumferential slot of the plurality of circumferential slots (21), as shown in FIG. 8. The energization of the plurality of coils (24) facilitates operation of the electric motor (300) or BLDC motor (300).
[47] According to an exemplary embodiment of the present disclosure, the optimum values of the plurality of stator teeth (23) are: the tooth width (tw) of each stator tooth (23)

is defined within a range of 1 - 1.5 mm. The tooth tang angle (ta) of each stator tooth (23) is defined within a range of 100° - 140°, as shown in FIG. 6. The tooth tip thickness (tb) of each stator tooth (23) is defined within a range of 0.5-1 mm. The stator core (20) is defined having an outer diameter (OD) and an inner diameter (ID). The outer diameter (OD) is defined within range of 27-28 mm and the inner diameter (ID) is defined within range of 10-11 mm. Each circumferential slot of the plurality of circumferential slots (21) are defined having a slot depth (Sd) and a slot opening width (Sw), as shown in FIG. 7. The slot depth (Sd) is defined within a range of 7-7.5 mm and the slot opening width (Sw) is defined within a range of 1.5-2.0 mm. The slot depth (Sd) may be defined as a distance between the tooth tip and an inner surface of the stator core (20). The slot opening width (Sw) may be defined as a distance between two adjacent tooth tips of two adjacent teeth of the stator core (20). In an exemplary embodiment, the plurality of stator teeth (23) are integrally formed with the stator core (20) of the stator assembly (200). The tooth width (tw) of each stator tooth of the plurality of stator teeth (23) may be defined as a width of the stator tooth extending from inner surface of the stator core (20). The tooth tip may be defined as a structure of the tooth formed proximity to the center of the stator core (20) and the tooth tip thickness (tb) may be defined as a thickness of the tooth tip. The tooth tang angle (ta) is defined as an angle formed between the tooth tip and tooth of the stator core (20).
[48] The above optimum values of the stator core (20) are defined for an exemplary purpose. However, the optimum values of the stator core (20) may slightly vary relative to the operating parameters of the BLDC motor (300) fitted to the fuel pump (100) and the hydraulic unit (40) and/or for any other reasons.
[49] Referring to FIG. 4, the hydraulic unit (40) comprises an impeller (41) housed inside the impeller housing (42), such that the impeller (41) is rotatably connected to the shaft (11) of the rotor assembly (10). The impeller (41) is rotatably connected to a lower end of the shaft (11) and an upper end of the shaft (11) is received in the upper bobbin unit (51) having bush (104) as an intermediate member between the shaft (11) and the upper bobbin unit (51). The impeller (41) is configured to rotate in accordance with the rotation

of the shaft (11) of the rotor assembly (10). The hydraulic unit (40) is provided to create sufficient suction pressure in order to govern flow of fuel stored in the fuel storage tank to the intake manifold of the engine. The optimum values of the stator core (20) is configured to operate the hydraulic unit (40) having more clearance between the impeller (41) and the impeller housing (42).
[50] Once again referring to FIG. 6, the plurality of circumferential slots (21) provided to the stator core (20) of the BLDC motor (300) are configured to accommodate large number of coils (24). The precisely designed dimensions of the stator core (20) lead to a thicker and longer BLDC motor (300) in comparison to that of convectional BLDC motors to govern operation of the hydraulic unit (40) coupled to the BLDC motor (300) of the fuel pump (100). The accommodation of plurality of coils (24) within each of the plurality of circumferential slots (21) generate required amount of flux to the rotor assembly (10) to get the desired amount of torque at the rated rpm. Further, the stator core (20) has enough cross-sectional area to avoid high flux density regions and to perform at high efficiency.
[51] In an embodiment of the present disclosure, stator is designed such that to allow the BLDC motor to have a smaller magnet compare to the conventional brushed DC motors and yet possesses the capability of running at the rated RPM value at predefined input current, generating the desired amount of torque, and operating at a high efficiency point.
[52] In an embodiment of the present disclosure, stator is designed in such a way to distribute the right amount of flux to the rotor, and to have low flux density throughout the cross-section, thus increasing the efficiency of the motor.
[53] In an embodiment of the present disclosure, the hydraulic unit is provided with high clearances to prevent clogging of impurities of the fuel in between the clearances and the electric motor with the stator assembly is configured to operate said hydraulic unit.

Equivalents:
[54] The embodiments herein and the various features and advantageous details thereof are explained with reference to the non-limiting embodiments in the description. Descriptions of well-known components and processing techniques are omitted so as to not unnecessarily obscure the embodiments herein. The examples used herein are intended merely to facilitate an understanding of ways in which the embodiments herein may be practiced and to further enable those of skill in the art to practice the embodiments herein. Accordingly, the examples should not be construed as limiting the scope of the embodiments herein.
[55] The foregoing description of the specific embodiments will so fully reveal the general nature of the embodiments herein that others can, by applying current knowledge, readily modify and/or adapt for various applications such specific embodiments without departing from the generic concept, and, therefore, such adaptations and modifications should and are intended to be comprehended within the meaning and range of equivalents of the disclosed embodiments. It is to be understood that the phraseology or terminology employed herein is for the purpose of description and not of limitation. Therefore, while the embodiments herein have been described in terms of preferred embodiments, those skilled in the art will recognize that the embodiments herein can be practiced with modification within the spirit and scope of the embodiments as described herein.
[56] Throughout this specification the word "comprise", or variations such as "comprises" or "comprising", will be understood to imply the inclusion of a stated element, integer or step, or group of elements, integers or steps, but not the exclusion of any other element, integer or step, or group of elements, integers or steps.
[57] The use of the expression "at least" or "at least one" suggests the use of one or more elements or ingredients or quantities, as the use may be in the embodiment of the disclosure to achieve one or more of the desired objects or results.

[58] Any discussion of documents, acts, materials, devices, articles and the like that has been included in this specification is solely for the purpose of providing a context for the disclosure. It is not to be taken as an admission that any or all of these matters form a part of the prior art base or were common general knowledge in the field relevant to the disclosure as it existed anywhere before the priority date of this application.
[59] The numerical values mentioned for the various physical parameters, dimensions or quantities are only approximations and it is envisaged that the values higher/lower than the numerical values assigned to the parameters, dimensions or quantities fall within the scope of the disclosure, unless there is a statement in the specification specific to the contrary.
[60] While considerable emphasis has been placed herein on the particular features of this disclosure, it will be appreciated that various modifications can be made, and that many changes can be made in the preferred embodiments without departing from the principles of the disclosure. These and other modifications in the nature of the disclosure or the preferred embodiments will be apparent to those skilled in the art from the disclosure herein, whereby it is to be distinctly understood that the foregoing descriptive matter is to be interpreted merely as illustrative of the disclosure and not as a limitation.

List of Reference Numerals:

Fuel pump 100
Terminals 101
Mounting rod 102
Non-return valve 103
Bush 104
Rotor assembly 10
Shaft 11
Magnet 12
Stator assembly 200
Electric motor 300
Stator core 20
Plurality of circumferential slots 21
Longitudinal slot 22
Plurality of stator teeth 23
Plurality of coils 24
Tooth tang angle ta
Tooth tip thickness tb
Tooth width tw
Slot opening width JW
Slot depth Sd
Inner diameter of stator core ID
Outer diameter of stator core OD
Housing 30
Inlet flange 31
Inlet port 31a
Outlet flange 32

Outlet port 32a
Hydraulic unit 40
Impeller 41
Impeller housing 42

Claims:
We Claim:

1. A stator assembly (200) for an electric motor (300), the assembly (200) comprising:
a stator core (20), wherein the stator core (20) comprises:
a plurality of circumferential slots (21) extending in a vertical direction and a longitudinal slot (22) extending along a longitudinal axis (X-X) of the stator core (20); wherein
each circumferential slot of the plurality of circumferential slots (21) are separated by plurality of stator teeth (23), wherein each stator tooth of the plurality of stator teeth (23) have optimized values of tooth width (tw), tooth tang angle (ta) and tooth tip thickness
(tb);
a plurality of coils (24) adapted to be received in each circumferential slot of the plurality of circumferential slots (21); and
wherein energization of the plurality of coils (24) facilitates operation of the electric motor (300).
2. The stator assembly (200) as claimed in claim 1, wherein the tooth width (tw) of each stator tooth (23) is defined within a range of 1 - 1.5 mm.
3. The stator assembly (200) as claimed in claim 1, wherein the tooth tang angle (ta) of each stator tooth (23) is defined within a range of 100° - 140°.
4. The stator assembly (200) as claimed in claim 1, wherein the tooth tip thickness (tb) of each stator tooth (23) is defined within a range of 0.5-1 mm.
5. The stator assembly (200) as claimed in claim 1, wherein the stator core (20) is defined having an outer diameter (OD) and an inner diameter (ID), wherein:
the outer diameter (OD) is defined within range of 27-28 mm; and the inner diameter (ID) is defined within range of 10-11 mm.

6. The stator assembly (200) as claimed in claim 1, wherein each circumferential slot of
the plurality of circumferential slots (21) are defined having a slot depth (Sd) and a slot
opening width (Sw), wherein:
the slot depth (Sd) is defined within a range of 7-7.5 mm; and
the slot opening width (Sw) is defined within a range of 1.5-2.0 mm.
7. The stator assembly (200) as claimed in claim 1, wherein the plurality of stator teeth (23) is integrally formed with the stator core (20) of the stator assembly (200).
8. A fuel pump (100) for a vehicle, the fuel pump (100) comprising:
an electric motor (300) and a hydraulic unit (40), wherein the hydraulic unit (40) is rotatably connected to the electric motor (300);
the electric motor (300) comprises a rotor assembly (10) and a stator assembly (200), wherein the rotor assembly (10) includes a shaft (11) and a magnet (12);
the stator assembly (200) as claimed in claim 1, wherein the stator assembly (200) and the rotor assembly (10) are enclosed within a housing (30); wherein
the magnet (12) of the rotor assembly (10) is rotatably received in the longitudinal slot (22) of the stator core (20) of the stator assembly (200), to facilitate rotation of the shaft (11) and thereby to facilitate operation of a hydraulic unit (40) coupled to the shaft (11) of the rotor assembly (10).
9. The fuel pump (100) as claimed in claim 8, wherein the hydraulic unit (40) comprises:
an impeller (41) housed inside the impeller housing (42), wherein the impeller (41) is rotatably connected to the shaft (11) of the rotor assembly (10).
10. The fuel pump (100) as claimed in claim 8, wherein the housing (30) comprises an inlet
flange (31) and an outlet flange (32); wherein:
the inlet flange (31) is disposed at a lower region of the housing (30) and the outlet flange (32) is disposed at an upper region of the housing (30).