Description:FIELD OF THE INVENTION

[1] The present disclosure generally relates to a saddle-type vehicle. More particularly, the present disclosure relates to a rear wheel drive assembly of a saddle-type vehicle.

BACKGROUND

[2] A saddle-type vehicle, for example an internal combustion engine (ICE) scooter or an electric scooter, includes a swingarm assembly which is a crucial part of the rear suspension system and powertrain. The swingarm connects the rear wheel of the scooter to the frame and allows the wheel to move up and down, absorbing shocks and bumps from the road. There are various types of swingarms. A single sided swingarm has a single arm pivoted at the scooter’s frame and supporting the rear wheel. The single sided swingarm allows easier rear wheel removal and hence provides better serviceability and maintenance. However, they are costlier to manufacture and relatively less stiff.

[3] A double sided swing arm has two swingarms, a right hand (RH) arm and a left hand (LH) arm. The double sided swing arm provides adequate stiffness and is easier to manufacture. However, the serviceability of a vehicle with double sided swing arm is not easy, especially when there is a gearbox attached to the rear wheel. First, the bolt and other associated components needs to be removed. Further, one of the arms, usually the RH arm will have to be removed in order to take out the rear wheel. Some swing arm configurations include both the arms integrated as a single unit with the connecting member. In such a swing arm configuration where both the LH and RH arms are integrated as a single unit, removal of a single arm, for example, the RH arm is not possible. This does not allow a gearbox to be attached to the rear wheel. This also makes the serviceability of the vehicle even more difficult.

[4] Therefore, there is a need for an assembly and a mechanism for easier serviceability for vehicles having double sided swing arm assembly.

SUMMARY

[5] This summary is provided to introduce a selection of concepts, in a simplified format, that is further described in the detailed description of the invention. This summary is neither intended to identify key or essential inventive concepts of the invention and nor is it intended for determining the scope of the invention.

[6] The main objective of the present disclosure is to provide a rear wheel drive assembly for easier serviceability of a saddle type vehicle.

[7] In an embodiment of the present disclosure, a rear wheel drive assembly for a saddle-type vehicle is disclosed. The rear wheel drive assembly includes a gearbox comprising a hollow output shaft, wherein the hollow output shaft comprises internal splines. The rear wheel drive assembly includes a rear wheel axle disposed partially along an axial direction in the hollow output shaft. The rear wheel axle comprise external splines rotatably engaged with the internal splines of the hollow output shaft. The rear wheel drive assembly includes a first swingarm member and a second swingarm member, wherein the second swingarm member is coupled to the rear wheel axle.

[8] To further clarify the advantages and features of the present invention, a more particular description of the invention will be rendered by reference to specific embodiments thereof, which are illustrated in the appended drawings. It is appreciated that these drawings depict only typical embodiments of the invention and are therefore not to be considered limiting of its scope. The invention will be described and explained with additional specificity and detail with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

[9] These and other features, aspects, and advantages of the present invention will become better understood when the following detailed description is read with reference to the accompanying drawings in which like characters represent like parts throughout the drawings, wherein:

[10] Figure 1 illustrates a perspective side view of a two-wheeler vehicle having, according to an embodiment of the present disclosure;

[11] Figure 2A illustrates a perspective view of a rear wheel drive assembly in a saddle-type vehicle, according to an embodiment of the present disclosure;

[12] Figure 2B illustrates an exploded view of the rear wheel drive assembly, according to an embodiment of the present disclosure;

[13] Figure 2C illustrates a perspective view of a rear wheel drive assembly in a saddle-type vehicle, according to an embodiment of the present disclosure;

[14] Figure 2D illustrates a front section view of a hollow output shaft with internal splines, according to an embodiment of the present disclosure;

[15] Figure 2E illustrates an isometric view of the hollow output shaft with the internal splines, according to an embodiment of the present disclosure;

[16] Figure 2F and Figure 2G illustrate the rear wheel axle with external splines, according to an embodiment of the present disclosure;

[17] Figure 2H illustrates a rear wheel hub, according to an embodiment of the present disclosure;

[18] Figure 2I illustrates isometric section view of the rear wheel hub with internal splines, according to an embodiment of the present disclosure;

[19] Figure 2J illustrates isometric section view of rear wheel axle, rear wheel hub and hollow output shaft, according to an embodiment of the present disclosure; and

[20] Figure 2K illustrates front section view of rear wheel axle, rear wheel hub and hollow output shaft, according to an embodiment of the present disclosure.

[21] Further, skilled artisans will appreciate that elements in the drawings are illustrated for simplicity and may not have necessarily been drawn to scale. For example, the flow charts illustrate the method in terms of the most prominent steps involved to help to improve understanding of aspects of the present invention. Furthermore, in terms of the construction of the vehicle, one or more components of the vehicle may have been represented in the drawings by conventional symbols, and the drawings may show only those specific details that are pertinent to understanding the embodiments of the present invention so as not to obscure the drawings with details that will be readily apparent to those of ordinary skill in the art having the benefit of the description herein.

DETAILED DESCRIPTION OF FIGURES

[22] For the purpose of promoting an understanding of the principles of the present disclosure, reference will now be made to the various embodiments and specific language will be used to describe the same. It will nevertheless be understood that no limitation of the scope of the present disclosure is thereby intended, such alterations and further modifications in the illustrated system, and such further applications of the principles of the present disclosure as illustrated therein being contemplated as would normally occur to one skilled in the art to which the present disclosure relates.

[23] It will be understood by those skilled in the art that the foregoing general description and the following detailed description are explanatory of the present disclosure and are not intended to be restrictive thereof.

[24] Whether or not a certain feature or element was limited to being used only once, it may still be referred to as “one or more features” or “one or more elements” or “at least one feature” or “at least one element.” Furthermore, the use of the terms “one or more” or “at least one” feature or element do not preclude there being none of that feature or element, unless otherwise specified by limiting language including, but not limited to, “there needs to be one or more…” or “one or more elements is required.”

[25] Reference is made herein to some “embodiments.” It should be understood that an embodiment is an example of a possible implementation of any features and/or elements of the present disclosure. Some embodiments have been described for the purpose of explaining one or more of the potential ways in which the specific features and/or elements of the proposed disclosure fulfil the requirements of uniqueness, utility, and non-obviousness.

[26] Use of the phrases and/or terms including, but not limited to, “a first embodiment,” “a further embodiment,” “an alternate embodiment,” “one embodiment,” “an embodiment,” “multiple embodiments,” “some embodiments,” “other embodiments,” “further embodiment”, “furthermore embodiment”, “additional embodiment” or other variants thereof do not necessarily refer to the same embodiments. Unless otherwise specified, one or more particular features and/or elements described in connection with one or more embodiments may be found in one embodiment, or may be found in more than one embodiment, or may be found in all embodiments, or may be found in no embodiments. Although one or more features and/or elements may be described herein in the context of only a single embodiment, or in the context of more than one embodiment, or in the context of all embodiments, the features and/or elements may instead be provided separately or in any appropriate combination or not at all. Conversely, any features and/or elements described in the context of separate embodiments may alternatively be realized as existing together in the context of a single embodiment.

[27] Any particular and all details set forth herein are used in the context of some embodiments and therefore should not necessarily be taken as limiting factors to the proposed disclosure.

[28] The terms “comprises”, “comprising”, or any other variations thereof, are intended to cover a non-exclusive inclusion, such that a process or method that comprises a list of steps does not include only those steps but may include other steps not expressly listed or inherent to such process or method. Similarly, one or more devices or sub-systems or elements or structures or components proceeded by “comprises... a” does not, without more constraints, preclude the existence of other devices or other sub-systems or other elements or other structures or other components or additional devices or additional sub-systems or additional elements or additional structures or additional components.

[29] Embodiments of the present disclosure will be described below in detail with reference to the accompanying drawings.

[30] For the sake of clarity, the first digit of a reference numeral of each component of the present disclosure is indicative of the Figure number, in which the corresponding component is shown. For example, reference numerals starting with digit “1” are shown at least in Figure 1. Similarly, reference numerals starting with digit “2” are shown at least in Figure 2.

[31] An Electric Vehicle (EV) or a battery powered vehicle including, and not limited to two-wheelers such as scooters, mopeds, motorbikes/motorcycles; three-wheelers such as auto-rickshaws, four-wheelers such as cars and other Light Commercial Vehicles (LCVs) and Heavy Commercial Vehicles (HCVs) primarily work on the principle of driving an electric motor using the power from the batteries provided in the EV. Furthermore, the electric vehicle may have at least one wheel which is electrically powered to traverse such a vehicle. The term ‘wheel’ may be referred to any ground-engaging member which allows traversal of the electric vehicle over a path. The types of EVs include Battery Electric Vehicle (BEV), Hybrid Electric Vehicle (HEV) and Range Extended Electric Vehicle. However, the subsequent paragraphs pertain to the different elements of a Battery Electric Vehicle (BEV).

[32] In construction, as illustrated in Figure 1, an EV (10) typically comprises a battery or battery pack (12) enclosed within a battery casing and includes a Battery Management System (BMS), an on-board charger (14), a Motor Controller Unit (MCU), an electric motor (16) and a transmission system (18). The primary function of the above-mentioned elements is detailed in the subsequent paragraphs: The battery of an EV (10) (also known as Electric Vehicle Battery (EVB) or traction battery) is re-chargeable in nature and is the primary source of energy required for the operation of the EV, wherein the battery (12) is typically charged using the electric current taken from the grid through a charging infrastructure (20). The battery may be charged using Alternating Current (AC) or Direct Current (DC), wherein in case of AC input, the on-board charger (14) converts the AC signal to DC signal after which the DC signal is transmitted to the battery via the BMS. However, in case of DC charging, the on-board charger (14) is bypassed, and the current is transmitted directly to the battery via the BMS.

[33] The battery (12) is made up of a plurality of cells which are grouped into a plurality of modules in a manner in which the temperature difference between the cells does not exceed 5 degrees Celsius. The terms “battery”, “cell”, and “battery cell” may be used interchangeably and may refer to any of a variety of different rechargeable cell compositions and configurations including, but not limited to, lithium-ion (e.g., lithium iron phosphate, lithium cobalt oxide, other lithium metal oxides, etc.), lithium-ion polymer, nickel metal hydride, nickel cadmium, nickel hydrogen, nickel-zinc, silver zinc, or other battery type/configuration. The term “battery pack” as used herein may be referred to multiple individual batteries enclosed within a single structure or multi-piece structure. The individual batteries may be electrically interconnected to achieve a desired voltage and capacity for a desired application. The Battery Management System (BMS) is an electronic system whose primary function is to ensure that the battery (12) is operating safely and efficiently. The BMS continuously monitors different parameters of the battery such as temperature, voltage, current and so on, and communicates these parameters to the Electronic Control Unit (ECU) and the Motor Controller Unit (MCU) in the EV using a plurality of protocols including and not limited to Controller Area Network (CAN) bus protocol which facilitates the communication between the ECU/MCU and other peripheral elements of the EV (10) without the requirement of a host computer.

[34] The MCU primarily controls/regulates the operation of the electric motor based on the signal transmitted from the vehicle battery, wherein the primary functions of the MCU include starting of the electric motor (16), stopping the electric motor (16), controlling the speed of the electric motor (16), enabling the vehicle to move in the reverse direction and protect the electric motor (16) from premature wear and tear. The primary function of the electric motor (16) is to convert electrical energy into mechanical energy, wherein the converted mechanical energy is subsequently transferred to the transmission system of the EV to facilitate movement of the EV. Additionally, the electric motor (16) also acts as a generator during regenerative braking (i.e., kinetic energy generated during vehicle braking/deceleration is converted into potential energy and stored in the battery of the EV). The types of motors generally employed in EVs include, but are not limited to DC series motor, Brushless DC motor (also known as BLDC motors), Permanent Magnet Synchronous Motor (PMSM), Three Phase AC Induction Motors and Switched Reluctance Motors (SRM).

[35] The transmission system (18) of the EV (10) facilitates the transfer of the generated mechanical energy by the electric motor (16) to the wheels (22a,22b) of the EV. Generally, the transmission systems (18) used in EVs include single speed transmission system and multi-speed (i.e., two-speed) transmission system, wherein the single speed transmission system comprises a single gear pair whereby the EV is maintained at a constant speed. However, the multi-speed/two-speed transmission system comprises a compound planetary gear system with a double pinion planetary gear set and a single pinion planetary gear set thereby resulting in two different gear ratios which facilitates higher torque and vehicle speed.

[36] In one embodiment, all data pertaining to the EV (10) and/or charging infrastructure (20) are collected and processed using a remote server (known as cloud) (24), wherein the processed data is indicated to the rider/driver of the EV (10) through a display unit present in the dashboard (26) of the EV (10). In an embodiment, the display unit may be an interactive display unit. In another embodiment, the display unit may be a non-interactive display unit.

[37] Embodiments of the present disclosure provide a rear wheel drive assembly in a saddle-type vehicle, for example, the electric vehicle (10). The saddle-type vehicle (10) includes a steering handle (30) mounted on a headtube.

[38] Figure 2A illustrates a perspective view of a rear wheel drive assembly (200) in a saddle-type vehicle (10), according to an embodiment of the present disclosure.

[39] The rear wheel drive assembly (200) includes a gearbox (205). Typically, a gearbox includes an input shaft and a solid output shaft. In the present disclosure, the gearbox (205) includes a hollow output shaft (210). Further, the hollow output shaft (210) includes internal splines (260). Figure 2D illustrates a front section view of the hollow output shaft (210) with the internal splines (260). Further, figure 2E illustrates an isometric view of the hollow output shaft (210) with the internal splines (260).

[40] The rear wheel drive assembly (200) includes a rear wheel axle (215) disposed partially along an axial direction in the hollow output shaft (210). Further, the rear wheel axle (215) is a rotatable floating axle. The rear wheel axle (215) includes external splines (265) rotatably engaged with the internal splines (260) of the hollow output shaft (210). Figure 2F and Figure 2G illustrates the rear wheel axle (215) with the external splines (265).

[41] Further, the rear wheel drive assembly (200) includes a first swingarm member (220A) and a second swingarm member (220B). The second swingarm member (220B) is coupled to the rear wheel axle (215). The rear wheel drive assembly (200) includes a rear wheel hub (225). Figure 2H illustrates the rear wheel hub (225). The rear wheel hub (225) includes internal splines (270). Figure 2I illustrates the rear wheel hub (225) with the internal splines (270). The external splines (265) of the rear wheel axle (215) is configured to engage with the internal splines (270) of the rear wheel hub (225). Figure 2J illustrates isometric section view of the rear wheel axle (215), the rear wheel hub (225) and the hollow output shaft (210). Further, figure 2K illustrates front section view of rear wheel axle (215), rear wheel hub (225) and the output shaft (210).

[42] The rear wheel drive assembly (200) includes a motor (230) coupled to the first swingarm member (220A) and an input shaft of the gearbox (205). The power generated in the motor (230) is transferred to rear wheel via the gearbox (205). The gearbox (205) is configured to increase or decrease speed based on the power generated in the motor. In one embodiment, the gearbox (205) is configured to transfer power from the engine of a scooter, for example, in ICE scooter.

[43] The rear wheel drive assembly (200) includes a plurality of support bearings. The plurality of support bearings include a first set of support bearings (235A) disposed between the hollow output shaft (210) and a gear box housing. The first set of support bearings (235A) can be disposed in more than one portion of the hollow output shaft (210). The gearbox housing is configured to house the gearbox (205). The plurality of support bearings include a second set of support bearings (235B) disposed between the rear wheel axle (215) and the second swingarm member (220B).

[44] The rear wheel drive assembly (200) includes a first nut (240) for clamping the rear wheel axle (215) to the hollow output shaft (210) of the gearbox (205). The rear wheel axle (215) includes a gearbox end (245A) and a second swingarm member end (245B). The gearbox end (245A) includes external thread to lock the rear wheel axle (215) to the first nut (240). The rear wheel drive assembly (200) includes a second nut (250) for clamping the second swingarm member (220B) to the rear wheel axle (215). It is to be noted that the first swingarm member (220A) and the second swingarm member (220B) is a single unit. Further, the first swingarm member (220A) and the second swingarm member (220B) are part of a double sided swingarm (255). The exploded view of the rear wheel drive assembly (200) having the double sided swingarm (255), the gearbox (205), the motor (230), the rear wheel hub (225) and the rear wheel axle (215) is illustrated in Figure 2B. Further, the rear wheel drive assembly (200) having the double sided swingarm (255) joined together with the gearbox (205), the motor (230), the rear wheel hub (225) and the rear wheel axle (215) is illustrated in Figure 2C.

[45] The rear wheel drive assembly (200) in the present disclosure can be used in any saddle-type vehicle. It can be used in Internal combustion engine scooters and bikes as well as electric scooters and bikes. The rear wheel drive assembly (200) provides easier serviceability of the rear wheel. The rear wheel axle (215) is a rotatable floating axle having splines to engage with two components, one is the gearbox (205) and the other being the rear wheel hub (225). Further, the gearbox (205) having splines can be attached to the rear wheel hub (225) using the rear wheel axle (215) and there is no need for removal of any components for servicing. This is achieved by removing the second nut (250) whereby the rear wheel axle (215) can be easily removed without disturbing any other components in the rear wheel drive assembly (200).

[46] In this application, unless specifically stated otherwise, the use of the singular includes the plural and the use of “or” means “and/or.” Furthermore, use of the terms “including” or “having” is not limiting. Any range described herein will be understood to include the endpoints and all values between the endpoints. Features of the disclosed embodiments may be combined, rearranged, omitted, etc., within the scope of the invention to produce additional embodiments. Furthermore, certain features may sometimes be used to advantage without a corresponding use of other features.

[47] List of reference numerals:
Components Reference numerals
Rear wheel drive assembly 200
Gearbox 205
Hollow output shaft 210
Rear wheel axle 215
First swingarm member 220A
Second swingarm member 220B
Rear wheel hub 225
Motor 230
First set of support bearings 235A
Second set of support bearings 235B
First nut 240
Second nut 250
Gearbox end 245A
Second swingarm member end 245B
Double sided swingarm 255
Internal splines 260
External splines 265
Internal splines 270

, Claims:1. A rear wheel drive assembly (200) for a saddle-type vehicle (10), the rear wheel drive assembly (200) comprising:
a gearbox (205) comprising a hollow output shaft (210), wherein the hollow output shaft (210) comprises internal splines (260);
a rear wheel axle (215) disposed partially along an axial direction in the hollow output shaft (210), wherein the rear wheel axle (215) comprise external splines (265) rotatably engaged with the internal splines (260) of the hollow output shaft (210); and
a first swingarm member (220A) and a second swingarm member (220B), wherein the second swingarm member (220B) is coupled to the rear wheel axle (215).

2. The rear wheel drive assembly (200) as claimed in claim 1, comprising:
a rear wheel hub (225) comprising internal splines (270), wherein the external splines (265) of the rear wheel axle (215) is configured to engage with the internal splines (270) of the rear wheel hub (225).

3. The rear wheel drive assembly (200) as claimed in claim 1, comprising:
a motor coupled (230) to the first swingarm member (220A) and an input shaft of the gearbox (205).

4. The rear wheel drive assembly (200) as claimed in claim 1, comprising a plurality of support bearings, wherein the plurality of support bearings comprise:
a first set of support bearings (235A) disposed between the hollow output shaft (210) and a gear box housing, wherein the gearbox housing is configured to house the gearbox (205); and
a second set of support bearings (235B) disposed between the rear wheel axle (215) and the second swingarm member (220B).

5. The rear wheel drive assembly (200) as claimed in claim 1, comprising a first nut (240) for clamping the rear wheel axle (215) to the hollow output shaft (210) of the gearbox (205).

6. The rear wheel drive assembly (200) as claimed in claim 5, wherein the rear wheel axle (215) comprises a gearbox end (245A) and a second swingarm member end (245B), wherein the gearbox end (245A) comprises external thread to lock the rear wheel axle (215) to the first nut (240).

7. The rear wheel drive assembly (200) as claimed in claim 1, comprising a second nut (250) for clamping the second swingarm member (220B) to the rear wheel axle (215).

8. The rear wheel drive assembly (200) as claimed in claim 1, wherein the first swingarm member (220A) and the second swingarm member (220B) is a single unit, wherein the first swingarm member (220A) and the second swingarm member (220B) are part of a double sided swingarm (255).

9. The rear wheel drive assembly (200) as claimed in claim 1, wherein the rear wheel axle (215) is a rotatable floating axle.