Straddle-type vehicle and its chassis

Abstract

Examples of a straddle-type vehicle and its chassis are disclosed. In one example, a straddle-type vehicle (100) includes a chassis (104), a drive member (110) for generating propulsion power, a power transmission component (112), and a driven member (114) for receiving the propulsion power from the drive member (110) through the power transmission component (112). The vehicle (100) may also have a swing arm (108) formed as having two parallel arms (116), a first end (118) pivotally connected to the chassis (104), and a second end (120) connected to the driven member (114). The drive member (110) is attached to the swing arm within a space (206) formed between the first end (118) of the swing arm (108), the driven member (114), and the two parallel arms (116).

Description

Technical Field

[0001] The present invention generally relates to vehicles, and more particularly to straddle-type vehicles.

Background Art

[0002] Straddle-type vehicles such as two-wheeled vehicles include a drive member such as an engine or a motor that provides a driving force to drive the vehicle. A transmission member is attached to the drive member, whereby the output power and torque generated by the drive member are transmitted to the wheels via a power transmission component such as a chain or a belt. Due to the torque and mechanical power transmitted to the wheels, the wheels move, and as a result, the straddle-type vehicle is propelled.

[0003] Conventionally, a straddle-type vehicle (hereinafter referred to as a vehicle) has a drive system that generates a towing force to move the vehicle. The vehicle is a two-wheeled vehicle, which can be an electric vehicle (EV), a hybrid electric vehicle (HEV), or an internal combustion (IC) engine-driven vehicle. The drive system includes a drive member such as an IC engine, an electric motor, or both. Although aspects related to conventional technologies and designs as well as the subject matter of the present invention have been discussed in the context of an electric motor being the drive member, it should also be understood that other types of drive systems such as an IC engine or a hybrid drive system are also considered to be part of it.

[0004] In certain cases, a hub motor is used to supply tractive power to a straddle-type vehicle. The hub motor is typically an electric motor coupled to the front wheel hub or rear wheel hub of the vehicle. However, the hub motor is a small-sized motor, and thus, its performance is low because the load capacity of the hub motor is also very low. In order to increase the power output and load capacity of the motor, a motor with a higher power output is used. Such a motor has a relatively large size, and this increased size may cause problems when mounting the motor on the wheel hub. As the size of the motor increases, mounting such a large-sized motor on the wheel hub makes the overall configuration around the wheel hub bulky. Also, packaging such a large-sized motor within a limited or restricted space may also become difficult and may even limit the operation of the wheel. Additionally, packaging other components or parts of the vehicle, such as brake rotors, brake drums, etc., within the same layout of the vehicle together with the large-sized motor within the wheel hub may also become difficult. In addition to this, the serviceability and maintenance of the motor are cumbersome because a mechanic or user is required to first remove the wheel and then access the motor.

[0005] In certain other conventional designs, for example, when the power output requirement from the drive member is high, the motor is mounted on the chassis of the vehicle instead of the wheel. In such a design, a transmission member is attached to the drive member, whereby the output power and torque generated by the drive member are transmitted to the wheel via power transmission components such as a chain, belt, gear train, etc. In one example, the transmission member may be a gear train, and power transmission components may not be required to transmit the output power to the wheel. When the torque and mechanical power generated by the drive member are transmitted to the wheel, the wheel is propelled. Thus, since the tractive power is generated through the drive member, the arrangement and configuration of the drive member play a very important role.

[0006] In such a conventional design, when the motor is attached to the chassis, in order to orient the motor so that the motor can be connected to the wheel for power transmission, a part of the motor may be attached to the fixed or stationary part of the chassis, i.e., on the main body of the chassis, and a part of the motor may have to be housed on the movable part of the chassis. For example, the motor can be attached to the swing arm of the vehicle that connects the chassis to the rear wheels of the vehicle. The swing arm is also coupled to, for example, the axle of the rear wheel and to the damper or shock absorber of the vehicle. In the riding state of the vehicle, the swing arm can move together with the rear wheel and the damper, and the part of the motor attached to the swing arm can move, but the other part of the motor attached to the chassis of the vehicle cannot move. As a result, the distance between the motor and the axle of the rear wheel continues to change, thereby bending the chain. As a result, the chain, which transmits the output power from the motor, can develop slack. The slack / sag in the chain can affect the conduction of power output from the motor to the swing arm and the rear wheel for traction. In addition to this, the durability of the chain can also be affected. Furthermore, to solve the problems mentioned above, simply attaching the motor to the movable part may not work, because it requires redesigning the entire chassis layout of the vehicle and reevaluating the packaging of the components of the vehicle, thereby requiring a lot of time and resources and being very costly. SUMMARY OF THE INVENTION PROBLEMS TO BE SOLVED BY THE INVENTION

[0007] The present invention relates to a straddle-type vehicle and aspects related to the chassis thereof, and more particularly, to aspects related to mounting a propulsion unit within a straddle-type vehicle and / or chassis, by way of example. MEANS FOR SOLVING THE PROBLEMS

[0008] The present invention discloses examples and aspects, in particular, to address the problems mentioned above. In one example, the present invention relates to a straddle-type vehicle such as a two-wheeler that can be an electric vehicle, a hybrid vehicle, or an internal combustion engine vehicle. According to one aspect, a straddle-type vehicle, which can be interchangeably referred to as a vehicle, may have a chassis that can serve as the main support structure of the vehicle and can bear all the stresses of the components assembled within the vehicle. In one example, the chassis may have a swing arm attachment portion for attaching a swing arm to which a propulsion unit is attached. The propulsion unit may include a drive member, a power transmission component, and a driven member.

Brief Description of the Drawings

[0009]

Fig. 1A

Fig. 1B

Fig. 2A

Fig. 2B

Modes for Carrying Out the Invention

[0010] A detailed description is provided with reference to the accompanying drawings. It should be noted that the description and the drawings are only examples of the present invention and do not mean to represent the present invention itself.

[0011] Throughout the drawings, the same reference numerals indicate elements that are similar but not necessarily identical. The drawings are not necessarily to scale, and the sizes of some parts may be exaggerated to show the illustrated examples more clearly. Further, the drawings provide examples and / or implementation forms consistent with the description, but the description is not limited to the examples and / or implementation forms provided in the drawings.

[0012] According to one example, the drive member generates propulsion power as an output that is transmitted to the driven member by a power transmission component. In an example where the transmission is achieved by a chain drive, a first transmission member attached to the drive member receives the output propulsion power from the driven member, and this output propulsion power is then transmitted to the driven member by the power transmission component. The transmission member may be a sprocket. In one example, the power transmission component may be a chain, and the driven member may have a second transmission member to receive the propulsion power. In one example, the driven member may be a vehicle wheel. Aspects related to the prior art and design, as well as the subject matter of the present invention, have been discussed in the context where the rear wheel is the driven member, but it should also be understood that the front wheel may also be considered a part of it. In one example, the drive member may include a transmission system such as an electric motor and a gearbox housed within the same housing. In another example, for applications that do not require torque multiplication, for example, the drive member may include only an electric motor.

[0013] In one example, the swing arm may have two parallel arms. The two parallel arms may have a first end and a second end. The first end may be pivotally connected to a swing arm attachment portion on the vehicle chassis, and the second end may be fixedly connected to a driven member of the vehicle. The swing arm attachment portion may be provided proximate to the center of the length of the chassis. According to one example, the swing arm attachment portion extending to a portion proximate to the center of the length of the vehicle chassis may, as a result, allow the length of the swing arm to be extended compared to a conventional assembly. Thus, a space is formed between the first end of the swing arm, the driven member (axle point of the wheel), and the two parallel arms of the swing arm. In one example, the drive member may be attached to the swing arm within the space formed between the first end of the swing arm, the driven member, and the two parallel arms of the swing arm. According to one example, the space formed between the first end of the swing arm, the driven member (axle point of the wheel), and the two parallel arms of the swing arm allows for the attachment of a drive member having an increased load capacity and an increased size, which may be possible without increasing the width of the vehicle or making any additional changes to the vehicle layout. As a result, since the drive member is packaged within the space thus formed, an increased space for attaching the vehicle battery may be left on the vehicle chassis. Alternatively, the increased space may also be used to package other components or parts of the vehicle within the same existing layout.

[0014] Furthermore, as disclosed above, where the first end of the swing arm is pivotally connected to a swing arm attachment portion on the vehicle chassis and the drive member is attached within the space formed as a result of such an assembly, the drive member may be attached closer to the center of the length of the chassis. Thus, since the drive member is attached closer to the center of the length of the chassis, the overall weight of the vehicle is concentrated at the center of the vehicle, thereby improving the vehicle's center of gravity. As a result, the handling of the vehicle can also be improved for the driver. Also, since the drive member is attached closer to the center of the length of the vehicle chassis, the mechanic / user may not have to perform the entire cumbersome process of removing all the wheels from the vehicle to access the drive member, thus making it easier to access the drive member for service and maintenance. According to the subject matter of the present invention, to access the drive member, the mechanic / user may need to remove the attachment member that attaches the drive member to the swing arm.

[0015] In addition, since the drive member is attached on the swing arm, the drive member, in a sense, becomes integrated with the swing arm. In other words, for example, when the swing arm moves during vehicle ride, the drive member may move as one unit with the swing arm and exhibit the same motion. According to one example, the power transmission components may also move within the same unit and exhibit the same motion as the swing arm. As a result, the durability of the chain is improved and the problems of slack and sag are resolved.

[0016] Furthermore, the attachment assembly of the drive member into the space formed within the swing arm closer to the driven member (rather than the vehicle chassis) reduces the length of the chain, i.e., the power transmission component. As a result, since the length is reduced, the transmission loss is substantially reduced and the lifespan of the power transmission component is further improved.

[0017] According to another aspect, the present invention discloses a chassis of a straddle-type vehicle, which is designed in particular to address the problems revealed above. The chassis may include a swing arm attachment portion that can be used to attach a swing arm to the chassis. The swing arm can have a propulsion unit attached thereto when assembled to the chassis. The chassis may further include a damper attachment portion that can be used to attach a damper connectable to the swing arm. When the swing arm and the damper are assembled or attached to the chassis, the swing arm and the damper are connected at a point where the axle of the wheel is also attached to the damper and the swing arm. Referring to the chassis, that point of connection of the swing arm and the damper is imaginary because it exists not on the chassis but within a space or region physically beyond the chassis. According to one example, the propulsion unit is attached between a point of the swing arm attachment portion within the region of the chassis and the imaginary point of connection of the swing arm and the damper. Such a configuration of the chassis can achieve the advantages revealed above of the subject matter of the present invention.

[0018] The above aspects are further shown in the figures and explained in the corresponding description below. It should be noted that the description and the figures merely illustrate the principles of the present invention. Therefore, various arrangements that include the principles of the present invention but are not explicitly described or illustrated in this specification may be contemplated from the description and are included within its scope.

[0019] FIG. 1A shows a side view of a straddle-type vehicle according to an example of the present invention. FIG. 1B shows a side perspective view of a straddle-type vehicle according to an example of the present invention. For the sake of brevity, FIGS. 1A and 1B are described in combination with each other.

[0020] The straddle-type vehicle 100 may have a propulsion unit 102. The straddle-type vehicle, hereinafter referred to as the vehicle, can be a two-wheeled vehicle which may be a hybrid vehicle, an electric vehicle (EV), an internal combustion (IC) engine vehicle, or the like. According to one aspect, the vehicle 100 may include a chassis 104 which can be the main support structure of the vehicle 100 and can support all the stresses of the components assembled in the vehicle 100. In one example, the chassis 104 may have a swing arm attachment portion 106 having a swing arm bracket (not shown) for attaching a swing arm 108 to which the propulsion unit 102 is attached. The propulsion unit 102 may include a drive member 110, a power transmission component 112, and a driven member 114. According to one example, the drive member 110 may include a transmission system such as an electric motor and a gearbox housed within the same housing. According to this example, the configuration of the drive member 110 may be such that the electric motor is housed together with the transmission system and can be vertically above the transmission system. In another example, for applications that do not require torque multiplication, for example, the drive member 110 may include only an electric motor. According to one aspect, the drive member 110 can generate propulsion power as an output transmitted to the driven member 114 by the power transmission component 112 for the vehicle 100 to move. According to one example, the driven member 114 may be the rear wheel 117 of the vehicle 100. In one example, the power transmission component 112 may be a chain. Although aspects related to technology and design as well as the subject matter of the present invention have been discussed in the context where the rear wheel 117 is the driven member 114, it should also be understood that the front wheel 122 is also considered to be a part thereof.

[0021] According to one aspect, the swing arm 108 may have two parallel arms 116. The two parallel arms 116 may have a first end 118 and a second end 120. According to an example, the first end 118 may be pivotally connected to the swing arm attachment portion 106 of the chassis 104 of the vehicle 100, and the second end 120 may be fixedly connected to the driven member 114 of the vehicle 100. The swing arm attachment portion 106 may be provided proximate to the center of the length of the chassis 104. According to an example, the swing arm 108 and the swing arm attachment portion 106 may extend to a portion proximate to the center of the length of the chassis 104 of the vehicle 100, and as a result, the length of the swing arm 108 may be extended. For this reason, a space (shown as 206 in FIG. 2A) may be formed between the first end 118 of the swing arm 108, the driven member 114, and the two parallel arms 116 of the swing arm 108. According to an example, the drive member 110 may be attached to the swing arm 108 within the formed space (shown as 206 in FIG. 2A). The drive member 110 may be attached onto the swing arm 108 by a fastener (shown as attachment point 204 in FIG. 2A).

[0022] According to another aspect, also as discussed above, the drive member 110 can generate propulsion power as the output power for the vehicle 100 to move. In an example where the transmission is achieved by the power transmission component 112, the transmission member 126 is attached to the drive member 110. According to one example, the first transmission member 126 may be attached near the drive member 110 to receive propulsion power as an output from the drive member 110, and this propulsion power is then transmitted to the driven member 114 by the power transmission component 112. According to other examples, the power transmission component 112 may be a belt (not shown) or a gear train (not shown). In one example, the power transmission component 112 may be a chain drive. According to one example, the driven member 114 may be the rear wheel 117 of the vehicle 100. The driven member 114 receives propulsion power through the second transmission member 128. According to one example, the transmission member 126 may be a sprocket (not shown). After receiving the propulsion power from the second transmission member 126, the rear wheel 117 starts to move, and as a result, the vehicle 100 can also move accordingly.

[0023] FIG. 2A shows a top perspective view of a propulsion unit of a straddle-type vehicle having a propulsion unit attached thereto, according to an example of the present invention. FIG. 2B shows a top exploded perspective view of the propulsion unit of the straddle-type vehicle having the propulsion unit attached thereto, according to an example of the present invention. For the sake of brevity, FIGS. 2A to 2B are described in combination with each other.

[0024] The straddle-type vehicle 100 may have a chassis 104 for attaching a propulsion unit 102. The straddle-type vehicle will hereinafter be referred to as the "vehicle". The chassis 104 may include a swing arm attachment portion 106 having a swing arm attachment bracket for attaching a swing arm 108 to the chassis 104. The swing arm 108 can have a propulsion unit 102 attached to the swing arm when assembled to the chassis 104. The chassis 104 may further include a damper attachment portion 200 that can be used to attach a damper 202 connectable to the swing arm 108. The damper 202 may be a dual shock absorber. The damper 202 can help improve the operability and handling of the driver's vehicle 100 while traveling over holes in the road surface or rough roads.

[0025] According to one aspect, when the swing arm 108 and the damper 202 are assembled or attached to the chassis 104, the swing arm 108 and the damper 202 are connected to a point 208 where the axle of the rear wheel (not shown in FIGS. 2A and 2B) is also attached to the damper 202 and the swing arm 108. Referring to the chassis 104, that point of connection of the swing arm 108 and the damper 202 is imaginary because it exists not on the chassis 104 but within a space or region physically beyond the chassis 104. According to one example, the propulsion unit 102 may be attached between a point of the swing arm attachment portion 106 within the region of the chassis 104 and the imaginary point 208 of connection of the swing arm 108 and the damper 202.

[0026] According to one example, the drive member 110 of the propulsion unit 102 may be attached through a plurality of attachment points 204-1, 204-2, 204-3, … 204-n. For the sake of brevity, the attachment points will hereinafter be collectively referred to as 204. The drive member 110 may be attached onto the swing arm 108 by a plurality of fasteners, bolts, screws, etc. The drive member 110 may be attached onto the swing arm 108 by three attachment points 204. According to one example, the drive member 110 may be attached onto the swing arm 108 by two attachment points 204. According to one example, at least one attachment point 204 may be on the swing arm attachment portion 106, and at least one attachment point 204 may be on each of the two parallel arms 116. When the drive member 110 is attached to the swing arm 108, it is supported from both sides by the two parallel arms 116 of the swing arm 108, thereby providing durability and rigidity to the drive member 110. In one example, the drive member 110 disposed between the two parallel arms 116 of the swing arm 108 may also provide structural support to the two parallel arms 116 of the swing arm 108. According to one example, the drive member 110 may be attached onto the swing arm 108 by fasteners, bolts, screws, etc.

[0027] According to one example, the swing arm 108 and the swing arm attachment portion 106 are extended to a vicinity of the center of the length of the chassis 104 of the vehicle 100. As a result, the space 206 is formed between the first end 118 of the swing arm 108, the driven member 114, and the two parallel arms 116 of the swing arm 108. As a result, since the swing arm attachment portion 106 is provided in proximity to the center of the length of the chassis 104, the length of the swing arm 108 can be extended as a result. According to one example, the first end 118 of the swing arm 108 is pivotally connected to the swing arm attachment portion 106 of the chassis 104 of the vehicle 100, and the drive member 110 is mounted within the space 206 formed as a result of such an assembly. Thus, the drive member 110 is mounted in proximity to the center of the length of the chassis 104 of the vehicle 100. Thus, mounting the drive member 110 in proximity to the center of the chassis 104 (where the weight of the vehicle 100 can be concentrated) thereby improves the center of gravity of the vehicle 100. As a result, the handling of the vehicle 100 can also be improved. Also, due to such a mounting assembly of the drive member 110, the mechanic / user may not have to perform the entire cumbersome process of removing the entire wheel to access the drive member, such as faced in a conventional arrangement where the drive member is mounted on the wheel hub. Thus, the mechanic / user may have easier access to the drive member 110 for performing service and maintenance. With the mounting assembly of the subject matter of the present invention, the mechanic / user can access the drive member 110 by removing the attachment point 204 that attaches the drive member 110 to the swing arm 108.

[0028] According to one example, the space 206 formed within the swing arm 108 enables the attachment of the drive member 110 having an increased load capacity and an increased size without any major changes to the conventional layout of the vehicle 100. As a result, since the drive member 110 is attached within the space 206 formed within the swing arm 108, such an attachment assembly of the drive member 110 frees up the space 206, and as a result, an increased space for attaching the battery 124 of the vehicle 100 (shown in FIG. 1A) remains in the chassis 104 of the vehicle 100. Alternatively, the increased space 206 may also be used to package other parts of the vehicle 100 (not shown) that may be required by the manufacturer / maintenance personnel / driver to improve the functionality or driving performance of the vehicle 100 and that can be easily packaged in the same layout.

[0029] According to one aspect, by attaching the drive member 110 within the space 206 formed within the swing arm 108, the drive member 110 is brought closer to the driven member 114 (rather than the chassis of the vehicle as proposed in the conventional subject matter), thereby reducing the length of the chain, i.e., the power transmission component 112. As a result, since the length is reduced, the transmission loss is substantially reduced, and the performance of the power transmission component 112 can be improved.

[0030] In one example, since the drive member 110 is attached to the swing arm, the drive member 110 will, in a sense, become integrated with the swing arm 108. In other words, for example, when the swing arm 108 moves during riding in the vehicle 100, the drive member 110 can also move as the same unit together with the swing arm 108 and can show the same movement. In other words, since the propulsion unit 102 is attached between the point of the swing arm attachment portion 106 and the imaginary point 208 within the area of the chassis 104, when the swing arm 108 moves, the propulsion unit 102 can also move in the same form. According to one example, the power transmission component 112 also moves within the same unit, shows the same movement as the swing arm 108, and as a result, the durability of the chain is improved and the problems of slack and sag are solved. In addition to this, the drive member 110 itself acts as a support or reinforcement member for the swing arm 108.

[0031] Although the implementation form of the straddle vehicle 100 has been described, it should be understood that the subject matter of the present invention is not necessarily limited to the specific features of the system or method or other aspects described herein. Instead, the specific features are disclosed as an implementation form of the attachment of the propulsion unit 102 within the straddle vehicle.

Claims

1. A straddle-type vehicle (100), wherein the vehicle is A chassis (104) having a swingarm mounting portion (106), A drive member (110) for generating propulsion power, Power transmission component (112) and A driven member (114) for receiving the propulsion power from the driving member (110) through the power transmission component (112), The swing arm (108) attached to the chassis (104) at the swing arm mounting portion (106), wherein the swing arm (108) is Two parallel arms (116) and A first end (118) pivotably connected to the chassis (104), It is formed having a second end (120) connected to the driven member (114), The drive member (110) comprises the first end (118) of the swing arm (108), the driven member (114), and the swing arm (108), which is attached to the swing arm in the space (206) formed between the two parallel arms (116). The driven member (114) is attached to the swing arm (108) at three mounting points (204). Straddle-type vehicle (100).

2. The straddle-type vehicle (100) according to claim 1, wherein the drive member (110) comprises an assembly of an electric motor and a transmission system.

3. The straddle-type vehicle (100) according to claim 2, wherein the transmission system is housed together with the electric motor.

4. The straddle-type vehicle (100) according to claim 1, wherein the drive member (110) has a plurality of mounting points (204) for attaching the drive member (110) to the swing arm (108).

5. The straddle-type vehicle (100) according to claim 1, wherein the swing arm mounting portion (106) is positioned close to the center of the length of the chassis (104).

6. The straddle-type vehicle (100) according to claim 1, wherein the drive member (110) is attached to the swing arm (108) in close proximity to the center of the length of the vehicle (100).

7. The straddle-type vehicle (100) according to claim 1, wherein the vehicle (100) is one of an electric vehicle, a hybrid electric vehicle, and an internal combustion (IC) engine-driven vehicle.

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