Description:FORM 2

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

COMPLETE SPECIFICATION
(See Section 10 and Rule 13)

Title of invention:
INTEGRATED SWINGARM ASSEMBLY WITH ACTIVE COOLING MECHANISM

Applicant:
River Mobility Private Limited
A company based in India,
Having its address as:
No. 25/3, KIADB EPIP Zone, Seetharampalya, Hoodi Road, Mahadevapura, Whitefield, Bengaluru, Karnataka, India- 560048

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

PRIORITY INFORMATION
[001] The present application is a patent of addition claiming priority from the parent application no. 202341052077 filed on 02nd August, 2023.
FIELD OF INVENTION
[002] The present invention generally relates to a swingarm assembly. More specifically, the present invention is related to an integrated swingarm assembly with a cooling mechanism for an electric vehicle.
BACKGROUND OF THE INVENTION
[003] The subject matter discussed in the background section should not be assumed to be prior art merely as a result of its mention in the background section. Similarly, a problem mentioned in the background section or associated with the subject matter of the background section should not be assumed to have been previously recognized in the prior art. The subject matter in the background section merely represents different approaches, which in and of themselves may also correspond to implementations of the claimed technology.
[004] A swingarm is used for connecting a rear wheel to a frame of a 2-wheeled vehicle. The swingarm allows vertical movement of the rear wheel, which provides better stability and control to the vehicle during acceleration, deceleration, and cornering. There exist different conventional mechanisms for mounting components on the swingarms.
[005] Some conventional arrangements utilize swingarm mounted motor-transmission assembly. Such conventional arrangements majorly utilize motors mounted within circumference of rear wheels. The motors are arranged in two layouts. A first layout includes installation of the hub motor without offset i.e. using the hub motor integrated with a wheel rim or using the hub motor with a planetary gear train system. A second layout includes installation of the motor with offset i.e. mounting the motor at an offset within a wheel circumference and coupling an input shaft with a wheel output shaft using a drivetrain system.
[006] There are several limitations associated with usage of the hub motors. One such limitation is related to its packaging and power sizing. Specifically, the hub motors installed with wheel rims are able to deliver less power because their power is constrained by size of the wheel rims. To increase the power capacity, size of the wheel rims is often required to be increased, and the increase in size of the wheel rims increases overall weight of unsprung mass. With offset type hub motors, size of the motor is constrained by the packaging i.e. space available on one side of the vehicle. Wheel rim offset is changed to package an offset type hub motor along with a gearbox and rear brake assembly in any vehicle.
[007] Another limitation associated with usage of the hub motors is thermal issues. As the hub motors are mounted within wheel rims, only natural cooling is available. Due to limited temperature drop gained from natural cooling, the hub motors operate at higher temperatures, which causes reduction in performance and efficiency of the hub motors. Similarly, for the offset type hub motors, proper cooling strategy is required to be designed to avoid thermal issues.
[008] Yet another limitation associated with usage of the hub motors is higher structural and shock loads. All road loads and shock loads get transferred to the hub motor through the rims. Therefore, motor mounting is to be made rigid to withstand the loads without undergoing any permanent deformation. Similarly, the offset type hub motors also have to withstand the shock loads, although the shock loads are slightly lesser. Internal components and casing mounting of the offset type hub motors are required to be designed to withstand such loads.
[009] Yet another limitation associated with usage of the hub motors is weight distribution and higher unsprung mass. Higher unsprung mass and rearward weight distribution is not desirable in terms of vehicle comfort and handling.
[0010] Some other conventional arrangements utilize chassis mounted motor-transmission assembly. In such conventional arrangements, the motor is mounted on a chassis as a sprung mass member. Driving force is transferred to a rear wheel through multi-stage or single-stage reduction drivetrains, based on the torque requirement of the rear wheel.
[0011] A limitation associated with usage of the chassis mounted motors is longer center distance drives. As the motor is mounted away from the rear wheel, longer center distance drives are required to be used. Tension variations arise in a belt or chain drive during up-down movement of the swingarm. Such tension variations affect Noise, Vibration, and Harshness (NVH) attributes of a vehicle.
[0012] Another limitation associated with usage of the chassis mounted motors is increased vehicle Center of Gravity (CG) height. Because a chassis mounted motor is mounted above a swingarm pivot point, the CG of the vehicle moves up. Such shifted CG usually affects maneuverability of the vehicle.
[0013] In view of the above mentioned shortcomings, there arises a need for a mechanism for mounting of motors and other necessary components in a vehicle using which the above mentioned limitations could be overcome.
[0014] In some convention arrangements, the motor is mounted on the chassis of the vehicle along with a motor controller. The motor is mounted within the closest proximity of the motor controller to avoid lengthy wiring harness usage of which results in loss in efficiency. However, such architecture results in certain issues, as mentioned above, such as the cooling issues and shift of CG of the vehicle.
[0015] In other conventional arrangements, where the motor is mounted on the swingarm within a wheel envelope i.e., motor mounted with slight offset to the wheel center, space constraint and feasibility of packaging the motor in close proximity of the motor controller becomes a challenge. Such arrangements also result in lengthy electrical connections and increased joule heat losses, and thus reduces efficiency of the system.
[0016] Further, because space is the biggest constraint in vehicles for packaging any cooling mechanisms, improving thermal performance of the system is a challenge.
[0017] Therefore, there arises a need for a solution for management of heat in the vehicles to overcome the above mentioned challenges.
OBJECTS OF THE INVENTION
[0018] A general objective of the invention is to provide a swingarm assembly which improves the center of gravity of a vehicle and thus improves the vehicle’s comfort and handling characteristics.
[0019] Another objective of the invention is to provide a swingarm assembly which offers uniform transfer of external forces to the chassis/frame of the vehicle.
[0020] Yet another objective of the invention is to provide a swingarm assembly which offers installation of a traction motor and drivetrain assembly on the vehicle. Relative motion from the ground to the wheel is inevitable which will cause the chassis to move relatively with suspension and swingarm bush as mount. By integrating the motor and drivetrain both the systems are isolated from such relative motion that are otherwise detrimental to durability and performance of the systems.
[0021] Yet another objective of the invention is to provide a swingarm assembly which allows a traction motor to deliver high power with lesser center distance between transmission components thereby minimising loss and increasing durability of the system.
[0022] Still another objective of the invention is to provide an integrated swingarm assembly with an active cooling mechanism for dissipation heat generated by a motor assembly.
[0023] Yet another objective of the invention is to provide vents or ducts in an integrated swingarm assembly to allow movement of air for heat dissipation.
[0024] Yet another objective of the invention is to improve performance of a motor assembly by dissipating heat generated by a motor assembly.
SUMMARY OF THE INVENTION
[0025] This summary is provided to introduce aspects related to a swingarm assembly for a vehicle, and the aspects are further described below in the detailed description. This summary is not intended to identify essential features of the claimed subject matter nor is it intended for use in determining or limiting the scope of the claimed subject matter.
[0026] In one embodiment, the swingarm assembly comprises a right swingarm, a left swingarm, and a traction motor positioned between the right swingarm and the left swingarm. The swingarm assembly further comprises a transmission assembly comprising power transferring elements enclosed within a housing. The housing is a recessed portion provided in at least one of the right swingarm and the left swingarm.
[0027] In one aspect, the power transferring elements include one of a chain drive, a belt and pulley drive, or a gearbox.
[0028] In one aspect, the gearbox comprises a plurality of gears selected from a driving gear and a driven gear.
[0029] In one aspect, the driving gear and the driven gear are coupled to each other and an endless transmission drive unit for transmitting driving force from the traction motor to a rear wheel. The endless transmission drive unit is one of a chain drive and a belt drive.
[0030] In one aspect, the swingarm assembly further comprises a transmission cover adapted to cover the transmission assembly enclosed within the housing.
[0031] In one aspect, an input shaft/hub of the transmission assembly is connected to the shaft of the traction motor and an output shaft/hub of the transmission assembly is in constant mesh with the input shaft/hub of the transmission assembly or an endless transmission drive unit.
[0032] In one aspect, the transmission assembly and the endless transmission drive unit are mounted towards a face of the traction motor, and together act as a two-stage speed reduction drivetrain assembly.
[0033] In one aspect, the transmission assembly acts as a primary speed reduction drive and the endless transmission drive unit acts as a secondary speed reduction drive.
[0034] In one aspect, the traction motor acting as a structural intermediate part is mounted between front ends of the right swingarm and the left swingarm, and is positioned closer to pivot points of the right swingarm and the left swingarm.
[0035] In one aspect, the traction motor forming the structural intermediate part is supported at the pivot points of the right swingarm and the left swingarm using sleeves, and press fitted silent block bushes are provided at both sides of the right swingarm and the left swingarm.
[0036] In one aspect, the silent block bushes dampen at least one of road loads, shock loads, and vibrations arising from the traction motor.
[0037] In one aspect, the traction motor forming the structural intermediate part is positioned or supported at the pivot points of the right swingarm and the left swingarm using motor mounts provided on the motor housing and bolted joints provided on either sides of the right swingarm and the left swingarm.
[0038] In one aspect, the endless transmission drive unit comprises one or more sprockets selected from a driving sprocket and a driven sprocket.
[0039] In one aspect, the output shaft of the transmission assembly is connected to the driving sprocket towards the face of the traction motor via a spline shaft connection.
[0040] In one aspect, the driven sprocket is connected to a rear wheel rim using bolted joints.
[0041] In one aspect, the transmission assembly comprises oil seals to prevent leakage of a lubricant used for the driving gear and the driven gear.
[0042] In one embodiment, the swingarm assembly for a vehicle comprises a right swingarm, a left swingarm, and a motor assembly positioned between the right swingarm and the left swingarm. The swingarm assembly further comprises a casing provided in at least one of the right swingarm and the left swingarm. The swingarm assembly further comprises a cooling module adapted to be enclosed in the casing to actively cool the motor assembly.
[0043] In one aspect, the motor assembly comprises at least one of a traction motor and a motor controller.
[0044] In one aspect, the casing of the right swingarm is adapted to enclose the cooling module and the casing of the left swingarm is adapted to enclose a transmission assembly.
[0045] In one aspect, the cooling module is at least one of an axial fan and a centrifugal fan.
[0046] In one aspect, the cooling module cools the motor assembly using a cooling agent.
[0047] In one aspect, the motor controller is mounted along a periphery of a motor housing or on either side of the motor housing.
[0048] In one aspect, the motor assembly comprises a front cover and a rear cover. At least one of the front cover and the rear cover covers at least a portion of the motor assembly.
[0049] In one aspect, air inlet vents are provided on an outer surface of the casing for housing the cooling module.
[0050] In one aspect, the cooling module draws air from the air inlet vents and directs the air towards the motor assembly.
[0051] In one aspect, the motor assembly and one of the right swingarm and the left swingarm housing the cooling module are separated by a first predefined distance forming a first gap. The first gap allows flow of cooled air from the cooling module over fins provided on a surface of the motor housing.
[0052] In one aspect, the front cover and the rear cover are separated by a second predefined distance forming a second gap, thereby exposing the motor controller and a portion of the motor. The second gap allows flow of air from a front end of a vehicle body towards a top side over fins provided on an exposed portion of one or more of the motor and the motor controller.
[0053] In one aspect, the front cover and the rear cover form an air-inlet channel or a duct for guiding air from the cooling module to flow over fins provided on a surface of the traction motor and the motor controller, thereby improving thermal performance of the motor assembly.
[0054] In one aspect, the transmission assembly comprises power transferring elements. The power transferring elements include one of a chain drive, a belt and pulley drive, or a gearbox.
[0055] In one aspect, the gearbox comprises a plurality of gears. The plurality of gears include at least one driving gear and at least one driven gear.
[0056] In one aspect, the driving gear and the driven gear are coupled to each other and an endless transmission drive unit for transmitting driving force from the traction motor of the motor assembly to a rear wheel.
[0057] In one aspect, the endless transmission drive unit is one of a chain drive and a belt drive.
[0058] Other aspects and advantages of the invention will become apparent from the following description, taken in conjunction with the accompanying drawings, illustrating by way of example the principles of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0059] The accompanying drawings constitute a part of the description and are used to provide a further understanding of the present invention.
[0060] Fig. 1a illustrates a left side view and Fig. 1b illustrates a right side view of a swingarm assembly mounted on a rear wheel of a vehicle, in accordance with an embodiment of the present invention.
[0061] Fig. 2 illustrates a left side view of the swingarm assembly integrated with a chassis of the vehicle, in accordance with an embodiment of the present invention.
[0062] Fig. 3a illustrates a front view of a left swingarm, in accordance with an embodiment of the present invention.
[0063] Fig. 3b illustrates a rear view of the left swingarm, in accordance with an embodiment of the present invention.
[0064] Fig. 4 illustrates a perspective front view of the swingarm assembly present in a disassembled condition, in accordance with an embodiment of the present invention.
[0065] Fig. 5 illustrates a perspective front view of the swingarm assembly present in an assembled condition, in accordance with an embodiment of the present invention.
[0066] Fig. 6 illustrates a perspective rear view of the swingarm assembly present in an assembled condition, in accordance with an embodiment of the present invention.
[0067] Fig. 7 illustrates an exploded view of the swingarm assembly, in accordance with an embodiment of the present invention.
[0068] Fig. 8 illustrates a perspective front view of a swingarm assembly present in a disassembled condition, in accordance with an embodiment of the present invention.
[0069] Fig. 9 illustrates a perspective front view of the swingarm assembly present in an assembled condition, in accordance with an embodiment of the present invention.
[0070] Fig. 10 illustrates an exploded view of the swingarm assembly, in accordance with an embodiment of the present invention.
[0071] Fig. 11a illustrates a perspective front view of the swingarm assembly and Fig. 11b illustrates a zoomed view of the swingarm assembly assembled with a main frame of a vehicle, in accordance with an embodiment of the present invention.
[0072] Fig. 12 illustrates a perspective front view of a swingarm assembly present in a disassembled condition, in accordance with an embodiment of the present invention.
[0073] Fig. 13 illustrates a perspective front view of the swingarm assembly present in an assembled condition, in accordance with an embodiment of the present invention.
[0074] Fig. 14 illustrates an exploded view of the swingarm assembly, in accordance with an embodiment of the present invention.
[0075] Fig. 15a illustrates a perspective front view of the swingarm assembly and Fig. 15b illustrates a zoomed view of the swingarm assembly assembled with a main frame of a vehicle, in accordance with an embodiment of the present invention.
[0076] Fig. 16 illustrates a perspective front view of a swingarm assembly present in a disassembled condition, in accordance with an embodiment of the present invention.
[0077] Fig. 17 illustrates a perspective front view of the swingarm assembly present in an assembled condition, in accordance with an embodiment of the present invention.
[0078] Fig. 18 illustrates an exploded view of the swingarm assembly, in accordance with an embodiment of the present invention.
[0079] Fig. 19a illustrates a perspective front view of a swingarm assembly and Fig. 19b illustrates a zoomed view of the swingarm assembly assembled with a main frame of a vehicle, in accordance with an embodiment of the present invention.
[0080] Figs. 20a and 20b illustrate longitudinal and transverse sections of swingarm assemblies showing flow of air for cooling, in accordance with an embodiment of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0081] The detailed description set forth below in connection with the appended drawings is intended as a description of various embodiments of the present invention and is not intended to represent the only embodiments in which the present invention may be practiced. Each embodiment described in this disclosure is provided merely as an example or illustration of the present invention, and should not necessarily be construed as preferred or advantageous over other embodiments. The detailed description includes specific details for the purpose of providing a thorough understanding of the present invention. However, it will be apparent to those skilled in the art that the present invention may be practiced without these specific details.
[0082] The present invention pertains to a swingarm assembly 100 for a vehicle. Fig. 1a illustrates a left side view and Fig. 1b illustrates a right side view of the swingarm assembly 100 mounted on a rear wheel 102 of the vehicle, in accordance with an embodiment of the present invention. Fig. 2 illustrates a left side view of the swingarm assembly 100 integrated with a rear end of a chassis 104 i.e. a main frame of the vehicle, in accordance with an embodiment of the present invention. Specifically, the swingarm assembly 100 may be integrated with the chassis 104 through a suspension 106 i.e. a shock absorber. Similarly, another suspension may be used for integrating the swingarm assembly 100 with the chassis 104 on the other side.
[0083] The swingarm assembly 100 comprises a left swingarm 302 and a right swingarm 304. The left swingarm 302 and the right swingarm 304 may be made of a strong and light material, such as aluminium. Fig. 3a illustrates a front view of the left swingarm 302 and Fig. 3b illustrates a rear view of the left swingarm 302, in accordance with an embodiment of the present invention. On the front side, the left swingarm 302 may comprise a housing 306 for enclosing one or more elements described successively with reference to Fig. 7.
[0084] Fig. 4 illustrates a perspective front view of the swingarm assembly 100 present in a disassembled condition, in accordance with an embodiment of the present invention. Figs. 5 and 6 illustrate perspective front and rear views of the swingarm assembly 100 present in an assembled condition, in accordance with an embodiment of the present invention.
[0085] Inner sides of the right swingarm 304 and the left swingarm 302 are designed to accommodate a traction motor 402 between them. The traction motor 402 acts as a structural intermediate part and is mounted between front ends of the right swingarm 304 and the left swingarm 302. The traction motor 402 may be positioned closer to pivot points 404 present on the right swingarm 304 and the left swingarm 302.
[0086] In one implementation, the traction motor 402 may be supported at the pivot points 404 of the right swingarm 304 and the left swingarm 302 using sleeves 602. The sleeves 602 with press fitted silent block bushes 700 (illustrated in Fig. 7) i.e. rubber bushings are provided at both sides of the right swingarm 304 and the left swingarm 302. The silent block bushes would dampen road loads, shock loads, and vibrations arising from the traction motor 402.
[0087] In another implementation, the traction motor 402 may be supported at the pivot points 404 of the right swingarm 304 and the left swingarm 302 using motor mounts provided on motor housing and bolted joints provided on either sides of the right swingarm 304 and the left swingarm 302.
[0088] Referring again to Fig. 5, the swingarm assembly 100 further comprises a transmission assembly 502. The transmission assembly 502 may be fixed on any of the right swingarm 304 and the left swingarm 302. The transmission assembly 502 may be covered by a transmission cover. The transmission cover may be present on an external side of any of the right swingarm 304 and the left swingarm 302. In one implementation, as shown in Fig. 5, the transmission assembly 502 and the transmission cover may be present on the external side of the left swingarm 302.
[0089] Fig. 7 illustrates an exploded view of the swingarm assembly 100, in accordance with an embodiment of the present invention. The transmission assembly 502 may comprise power transferring elements enclosed within a housing 306 i.e. a recessed portion provided in at least one of the right swingarm 304 and the left swingarm 302. The power transferring elements may include a chain drive, a belt and pulley drive, or a gearbox. The gearbox may comprise a plurality of gears, such as a driving gear 704 and a driven gear 706. The gearbox may be covered using a gearbox cover 702 to prevent ingress of contaminants like dirt and water into the gearbox.
[0090] The driving gear 704 and the driven gear 706 may be coupled to each other and an endless transmission drive unit 708. The endless transmission drive unit 708 comprises one or more sprockets, such as a driving sprocket 710 and a driven sprocket 712. The endless transmission drive unit 708 may allow transmission of driving force from the traction motor 402 to the rear wheel 208. The endless transmission drive unit 708 may be a chain drive or a belt drive.
[0091] An input shaft/hub of the transmission assembly 502 i.e. the driving gear 704 may be connected to the shaft/hub of the traction motor 402. Further, an output shaft of the transmission assembly 502 i.e. the driven gear 706 may be in constant mesh with the input shaft/hub i.e. the driving gear 704 of the transmission assembly 502 or an endless transmission drive unit 708.
[0092] As visible in Figs. 5 through 7, the transmission assembly 502 and the endless transmission drive unit 708 are mounted towards the face of the traction motor 402. The transmission assembly 502 and the endless transmission drive unit 708 may together act as a two-stage speed reduction drivetrain assembly. Specifically, the transmission assembly 502 acts as a primary speed reduction drive and the endless transmission drive unit 708 acts as a secondary speed reduction drive.
[0093] The output shaft of the transmission assembly i.e. the driven gear 706 is connected to the driving sprocket 710 towards a face of the traction motor 402 via a spline shaft connection. The driven sprocket 712 may be connected to a rear wheel rim 714 using bolted joints.
[0094] The transmission assembly 502 may further comprise one or more oil seals 716 to prevent leakage of a lubricant used for the driving gear 704 and the driven gear 706.
[0095] The swingarm assembly described above offers several technical advantages. A few such technical advantages are mentioned henceforth.
[0096] Although the traction motor is mounted on the swingarm as an unsprung mass, the traction motor is located closer to the pivot points of the swingarm. Because of such positioning, the entire weight of the traction motor will not act as unsprung mass, and the vehicle’s comfort and handling characteristics get improved.
[0097] The weight of the traction motor gets concentrated near the Center of Gravity (CG) of the vehicle which helps in weight distribution of the vehicle, hence improves dynamics of the vehicle. The traction motor could also be mounted closer to ground i.e. below the pivot points to further reduce the CG of the vehicle.
[0098] Vertical movement of the swingarm assembly due to road irregularities will impart less shock loads and vibration loads on the traction motor as the traction motor is mounted closer to the pivot point and thus less displacement of the traction motor occurs along a vertical axis.
[0099] Because the traction motor is coupled with the chassis i.e. the main frame using rubber bushing press fitted into swingarm eyes, vibrations arising due to dynamics of the traction motor get reduced. Further, NVH characteristics are improved and transfer of vibrations to driver’s tactile points such as foot rest, floor board, seat, and handlebar is reduced.
[00100] As different suspensions can be used on each side of the swingarm assembly, forces acting on the vehicle are distributed uniformly to its main frame.
[00101] A gearbox assembly integrated with the swingarm can be used with traction motors having different form and power factors by keeping the same architecture. This allows scaling up and evolution of similar variants of the architecture.
[00102] Fig. 8 illustrates a perspective front view of a swingarm assembly 800 present in a disassembled condition, in accordance with an embodiment of the present invention. Fig. 9 illustrates a perspective front view of the swingarm assembly 800 present in an assembled condition, in accordance with an embodiment of the present invention. Fig. 10 illustrates an exploded view of the swingarm assembly 800, in accordance with an embodiment of the present invention. Referring now to Fig. 8, Fig. 9, and Fig. 10, the structure of the swingarm assembly 800 and the components of the swingarm assembly 800 have been described successively. The swingarm assembly 800 may comprise a left swingarm 802 and a right swingarm 804. Further, a motor assembly may be positioned between the left swingarm 802 and the right swingarm 804. The motor assembly may include the traction motor 402. The swingarm assembly 800 may further comprise a cooling module 806 to actively cool the motor assembly. The cooling module 806 may be adapted to be enclosed in a casing provided in at least one of the left swingarm 802 and the right swingarm 804.
[00103] In one implementation, a casing 808 of the right swingarm 804 may be adapted to enclose the cooling module 806 and a casing 810 of the left swingarm 802 may be adapted to enclose the transmission assembly 502. In another implementation, the casing 808 of the right swingarm 804 may be adapted to enclose the transmission assembly 502 and the casing 810 of the left swingarm 802 may be adapted to enclose the cooling module 806.
[00104] The cooling module 806 may be an axial fan or a centrifugal fan. The cooling module 806 cools the motor assembly using a cooling agent, such as natural/ambient air.
[00105] The motor assembly comprises a front cover 812 and a rear cover 814. At least one of the front cover 812 and the rear cover 814 covers at least a portion of the motor assembly.
[00106] Further, air inlet vents 902 (illustrated in Fig. 9) are provided on an outer surface of the casing 808 of the right swingarm 804. The cooling module 806 housed in the casing 808 draws air from the air inlet vents 902 and directs the air towards the motor assembly. Likewise, the air inlet vents may be provided on an outer surface of the casing 810 of the left swingarm 802 when the cooling module 806 is housed in the casing 810 of the left swingarm 802.
[00107] Fig. 11a illustrates the perspective front view of the swingarm assembly 800 and Fig. 11b illustrates a zoomed view of the swingarm assembly 800 assembled with a main frame 1100 of a vehicle, in accordance with an embodiment of the present invention. Assembling the swingarm assembly 800 with the main frame 1100 results in an even distribution of weight and maintaining structural rigidity of the swingarm assembly 800.
[00108] The swingarm assembly 800 described above offers several technical advantages, such as the ones mentioned henceforth. The cooling module provided in the swingarm assembly 800 can be integrated with motors of different form factors to operate effectively near peak power envelopes of motor characteristic curves. The fan packaged within the swingarm allows sufficient flow of air over the motor housing equipped with the cooling fins for effective heat transfer. With such arrangements, the traction motor can operate with optimum efficiency as the operating temperature is controlled using the forced/external cooling system.
[00109] Fig. 12 illustrates a perspective front view of a swingarm assembly 1200 present in a disassembled condition, in accordance with an embodiment of the present invention. Fig. 13 illustrates a perspective front view of the swingarm assembly 1200 present in an assembled condition, in accordance with an embodiment of the present invention. Fig. 14 illustrates an exploded view of the swingarm assembly 1200, in accordance with an embodiment of the present invention. Referring now to Fig. 12, Fig. 13, and Fig. 14, the structure of the swingarm assembly 1200 and the components of the swingarm assembly 1200 have been described successively.
[00110] The motor assembly further comprises a motor controller 1202 configured to control operation of the traction motor 402. The motor controller 1202 may be mounted along a periphery of a motor housing i.e. body of the traction motor 402 or on either side of the motor housing.
[00111] Further, the air inlet vents 902 (illustrated in Fig. 13) may be provided on the outer surface of the casing 808 of the right swingarm 804. The air inlet vents 902 enables natural movement of ambient air towards the motor assembly for cooling the motor assembly including the traction motor 402 and the motor controller 1202.
[00112] Fig. 15a illustrates a perspective front view of the swingarm assembly 1200 and Fig. 15b illustrates a zoomed view of the swingarm assembly 1200 assembled with a main frame 1500 of a vehicle, in accordance with an embodiment of the present invention. Assembling the swingarm assembly 1200 with the main frame 1500 results in an even distribution of weight and maintaining structural rigidity of the swingarm assembly 1200.
[00113] The swingarm assembly 1200 described above offers several technical advantages, such as the ones mentioned henceforth. The air inlet vents provided on the outer surface of the casing allows sufficient flow of air over the motor housing equipped with the cooling fins for effective heat transfer. With such arrangement, the traction motor can operate with optimum efficiency as the operating temperature is controlled using the natural cooling system.
[00114] Further, mounting the motor controller in close proximity to the traction motor offers reduction in length of high voltage wires, and thus improves efficiency of the system by reducing the heat losses arising due to flow of high current. Further, due to close placement of the motor controller and the traction motor, the need of providing separate cooling arrangements is avoided. Also, mounting the motor controller over the periphery of the motor housing improves the structural integrity of the traction motor and adds stiffness to the swingarm assembly of the vehicle.
[00115] Fig. 16 illustrates a perspective front view of a swingarm assembly 1600 present in a disassembled condition, in accordance with an embodiment of the present invention. Fig. 17 illustrates a perspective front view of the swingarm assembly 1600 present in an assembled condition, in accordance with an embodiment of the present invention. Fig. 18 illustrates an exploded view of the swingarm assembly 1600, in accordance with an embodiment of the present invention. Referring now to Fig. 16, Fig. 17, and Fig. 18, the structure of the swingarm assembly 1600 and components of the swingarm assembly 1600 have been described successively.
[00116] The motor assembly positioned between the left swingarm 802 and the right swingarm 804 may include the traction motor 402 and the motor controller 1202. Further, the cooling module 806 enclosed in the casing 808 may be used to actively cool the motor assembly i.e. the traction motor 402 and the motor controller 1202.
[00117] The motor assembly may further comprise the front cover 812 and the rear cover 814. At least one of the front cover 812 and the rear cover 814 may cover at least a portion of the motor assembly.
[00118] Further, the air inlet vents 902 (illustrated in Fig. 17) are provided on an outer surface of the casing 808 of the right swingarm 804. The cooling module 806 housed in the casing 808 draws air from the air inlet vents 902 and directs the air towards the motor assembly.
[00119] Fig. 19a illustrates a perspective front view of the swingarm assembly 1600 and Fig. 19b illustrates a zoomed view of the swingarm assembly 1600 assembled with a main frame 1900 of a vehicle, in accordance with an embodiment of the present invention. Assembling the swingarm assembly 1600 with the main frame 1900 results in an even distribution of weight and maintaining structural rigidity of the swingarm assembly 1600.
[00120] The swingarm assembly 1600 described above offers several technical advantages, such as the ones mentioned henceforth. The cooling module provided in the swingarm assembly 1600 can be integrated with motors of different form factors to operate effectively near peak power envelopes of motor characteristic curves. The fan packaged within the swingarm allows sufficient flow of air over the motor housing equipped with the cooling fins for effective heat transfer. With such arrangements, the motor can operate with optimum efficiency as the operating temperature is controlled using the forced/external cooling system.
[00121] Mounting the motor controller in close proximity to the motor offers reduction in length of high voltage wires, and thus improves efficiency of the system by reducing the heat losses arising due to flow of high current. Further, due to close placement of the motor controller and the motor, a single cooling module is sufficient and the need of providing separate cooling modules is avoided. Also, mounting the motor controller over the periphery of the motor housing improves the structural integrity of the motor and adds stiffness to the swingarm assembly of the vehicle.
[00122] Fig. 20a illustrates a longitudinal section of the swingarm assembly 1200 showing flow of air 2000 for cooling, in accordance with an embodiment of the present invention. As shown in Fig. 20a, the air 2000 may flow from the front end of the vehicle body and towards a top side over fins provided on an exposed portion of the traction motor 402 and fins present beneath the motor controller 1202.
[00123] Fig. 20b illustrates a transverse section of the swingarm assembly 800 showing flow of air 2002 for cooling, in accordance with an embodiment of the present invention. As shown in Fig. 20b, the air 2002 flows from the cooling module 806 through an air-inlet channel or a duct formed between cooling fins 2003 of the motor housing or the motor assembly, and the front and rear covers. Specifically, the air 2002 flows through a duct 2004 formed between the cooling fins 2003 of the motor housing or the motor assembly, and the front cover 812. Further, the air 2002 also flows through a duct 2006 formed between the cooling fins 2003 of the motor housing or the motor assembly, and the rear cover 814.
[00124] Further, the motor assembly and one of the right swingarm 804 and the left swingarm 802 housing the cooling module 806 are separated by a first predefined distance forming a first gap 2008 (illustrated in Fig. 20b). The first gap 2008 allows flow of the air 2002 from the cooling module 806 towards the motor assembly. More specifically, the first gap 2008 allows flow of air 2002 from the cooling module 806 over the cooling fins 2003 provided on the surface of at least one of the motor and motor controller housings.
[00125] The front cover 812 and the rear cover 814 are separated by a second predefined distance forming a second gap 2010 (illustrated in Fig. 20a), to expose the motor controller 1202 and a portion of the traction motor 402. The second gap 2010 allows flow of air from the front end of the vehicle body towards the top side over fins provided on an exposed portion of one or more of the traction motor 402 and the motor controller 1202.
[00126] The front cover 812 and the rear cover 814 also form the air-inlet channel or the duct for guiding the air from the cooling module 806 to flow over the fins provided on a surface of the traction motor 402 and the motor controller 1202, to improve thermal performance of the motor assembly.
[00127] Although implementations of the swingarm assembly have been described in language specific to structural features and/or methods, it is to be understood that the appended claims are not necessarily limited to the specific features or methods described. Rather, the specific features or methods are disclosed as examples of implementations of the swingarm assembly.
, Claims:We Claim:
1. A swingarm assembly (800, 1200, 1600) for a vehicle, comprising:
a right swingarm (804);
a left swingarm (802);
a motor assembly positioned between the right swingarm (804) and the left swingarm (802);
a casing (808) provided in at least one of the right swingarm (804) and the left swingarm (802); and
a cooling module (806) adapted to be enclosed in the casing (808) to actively cool the motor assembly.
2. The swingarm assembly (800, 1200, 1600) as claimed in claim 1, wherein the motor assembly comprises at least one of a traction motor (402) and a motor controller (1202).
3. The swingarm assembly (800, 1200, 1600) as claimed in claim 1, wherein the casing (808) of the right swingarm (804) is adapted to enclose the cooling module (806) and the casing (810) of the left swingarm (802) is adapted to enclose a transmission assembly (502).
4. The swingarm assembly (800, 1200, 1600) as claimed in claim 1, wherein the cooling module (806) is at least one of an axial fan and a centrifugal fan.
5. The swingarm assembly (800, 1200, 1600) as claimed in claims 1 and 2, wherein the cooling module (806) cools the motor assembly using a cooling agent.
6. The swingarm assembly (800, 1200, 1600) as claimed in claim 2, wherein the motor controller (1202) is mounted along a periphery of a motor housing or on either side of the motor housing.
7. The swingarm assembly (800, 1200, 1600) as claimed in claim 2, wherein the motor assembly comprises a front cover (812) and a rear cover (814), wherein at least one of the front cover (812) and the rear cover (814) covers at least a portion of the motor assembly.
8. The swingarm assembly (800, 1200, 1600) as claimed in claim 1, further comprising air inlet vents (902) provided on an outer surface of the casing (808) for housing the cooling module (806).
9. The swingarm assembly (800, 1200, 1600) as claimed in claim 8, wherein the cooling module (806) draws air from the air inlet vents (902) and directs the air towards the motor assembly.
10. The swingarm assembly (800, 1200, 1600) as claimed in claim 1, wherein the motor assembly and one of the right swingarm (804) and the left swingarm (802) housing the cooling module (806) are separated by a first predefined distance forming a first gap (2008), and wherein the first gap (2008) allows flow of cooled air from the cooling module (806) over cooling fins (2003) provided on a surface of the motor housing.
11. The swingarm assembly (800, 1200, 1600) as claimed in claim 7, wherein the front cover (812) and the rear cover (814) are separated by a second predefined distance forming a second gap (2010), thereby exposing the motor controller (1202) and a portion of the traction motor (402), and wherein the second gap (2010) allows flow of air from a front end of a vehicle body towards a top side over fins provided on an exposed portion of one or more of the traction motor (402) and the motor controller (1202).
12. The swingarm assembly (800, 1200, 1600) as claimed in claims 7 through 9, wherein the front cover (812) and the rear cover (814) forms an air-inlet channel for guiding air from the cooling module (806) to flow over fins provided on the surface of the traction motor (402) and the motor controller (1202), thereby improving thermal performance of the motor assembly.
13. The swingarm assembly (800, 1200, 1600) as claimed in claim 3, wherein the transmission assembly (502) comprises power transferring elements, the power transferring elements include one of a chain drive, a belt and pulley drive, or a gearbox.
14. The swingarm assembly (800, 1200, 1600) as claimed in claim 13, wherein the gearbox comprises a plurality of gears, the plurality of gears include at least one driving gear (704) and at least one driven gear (706).
15. The swingarm assembly (800, 1200, 1600) as claimed in claim 14, wherein the driving gear (704) and the driven gear (706) are coupled to each other and an endless transmission drive unit (708) for transmitting driving force from a traction motor (402) of the motor assembly to a rear wheel (208).
16. The swingarm assembly (800, 1200, 1600) as claimed in claim 15, wherein the endless transmission drive unit (708) is one of a chain drive and a belt drive.