Hybrid powertrain system

Abstract

The present disclosure provides a transmission system for a straddle-type hybrid vehicle, the transmission system including an internal combustion engine having a crankshaft. A first electric motor is configured to drive the crankshaft. An input shaft is in driving connection with the crankshaft. A second electric motor is in driving connection with a drive shaft. A transmission is configured to transmit rotational driving force between the input shaft and the drive shaft at a plurality of speed ratios. The present disclosure also provides a controller for a transmission system of a straddle-type hybrid vehicle. The present disclosure also provides a straddle-type vehicle having the transmission system and / or the controller of the present disclosure.

Description

Technical Field

[0001] This invention relates to a hybrid powertrain system for a motorcycle-type vehicle. Specifically, this invention relates to a hybrid powertrain system having two electric motors and one internal combustion engine. Background Technology

[0002] Hybrid electric vehicles (HEVs) consist of an internal combustion engine and at least one electric motor. They combine the instantaneous torque, improved acceleration, and regenerative braking capabilities of an electric motor with the extended range and power output of an internal combustion engine. In motorcycles, space and weight constraints are greater compared to automobiles. The additional space required for the electric motor, battery, and potentially complex transmission can make integrating a hybrid powertrain into a motorcycle challenging.

[0003] U.S. Patent No. 11,607,945 discloses a hybrid vehicle having an engine, an electric motor, a power transmission shaft, and a slidable switching claw clutch to disconnect the power transmission route. Chinese Patent Publication No. 110329058A discloses a clutchless multi-gear dynamic coupling mechanism suitable for plug-in hybrid electric vehicles, comprising an engine, a first drive motor and a second drive motor, multiple gear pairs, and four synchronizers. U.S. Patent No. 10,479,188 discloses a hybrid transmission for a motor vehicle including two concentric input shafts connected to a thermal engine crankshaft and a non-disengaging electric motor.

[0004] The object of the present invention is to provide an improved hybrid powertrain for motorcycles to solve at least some of the problems mentioned above. Summary of the Invention

[0005] Embodiments of this disclosure aim to provide a drivetrain for a straddle-type hybrid vehicle, the drivetrain including any or all of the following features: an internal combustion engine including a crankshaft; a first electric motor configured to drive the crankshaft; an input shaft drivenly connected to the crankshaft; a second electric motor drivenly connected to the drive shaft; and a transmission configured to transmit rotational driving force between the input shaft and the drive shaft at multiple speed ratios.

[0006] This arrangement provides a P1 / P3 hybrid architecture for motorcycles, for example, without the need for a clutch to disconnect the engine from the transmission's input shaft. This can offer the advantages of reduced motorcycle cost and weight, while providing more available space for the battery or fuel tank, thereby increasing the motorcycle's range.

[0007] In this paper, the term "transmissional connection" can be understood as two components permanently arranged such that rotation of one component causes rotation of the other, and vice versa. This contrasts with "transmissionable connection" between two components, in which the components can be selectively configured to transmit rotational driving force between them.

[0008] The rotor of the first motor can be directly connected to the crankshaft. This direct connection likely means there is no intermediate medium between the first motor and the crankshaft. By omitting any transmission shaft between the first motor and the crankshaft, the encapsulation efficiency of the drivetrain can be further improved.

[0009] The transmission system can be a clutchless transmission system. The second motor may include a rotor that is driven to the drive shaft. The rotor may be driven to the drive shaft via a first gear pair. This can further improve the encapsulation of the transmission within the transmission system.

[0010] The crankshaft, input shaft, and drive shaft can be integrated within the crankcase. This offers the advantage of housing the crankshaft and transmission shafts in a single housing.

[0011] The crankcase may include at least one opening. The at least one opening may be configured to receive at least one of the following: a piston shaft of an internal combustion engine; a rotary drive element of a first electric motor; and a rotary drive element of a second electric motor. This arrangement allows components of the internal combustion engine and the electric motor to mate with the transmission.

[0012] The crankshaft may be adjacent to at least one of the input shaft and the drive shaft. The crankshaft may also be adjacent to at least one of the input shaft and the drive shaft in a direction perpendicular to the crankshaft's axis of rotation. Instead of the existing arrangement where the internal combustion engine and transmission are positioned in series, this arrangement offers the advantage of arranging the crankshaft and other shafts in parallel, which can improve the compactness of the drivetrain.

[0013] The crankshaft's axis of rotation can be collinear with the axis of rotation of the first motor. This offers the advantages of more efficient packaging and a reduction in the number of components in the drivetrain.

[0014] The axes of rotation of the crankshaft, input shaft, and drive shaft can be parallel to each other. These axes of rotation can be arranged in a triangular array. This can advantageously reduce the overall height of the transmission.

[0015] The second motor can be driven by the drive shaft via an intermediate shaft. The intermediate shaft can be collinear with the input shaft. The intermediate shaft can be concentric with the input shaft. The intermediate shaft can be driven by the drive shaft via a gear located at the end of the intermediate shaft opposite to the second motor. Since the second motor may have a relatively large diameter, this positioning offers the advantage of reducing the extent to which the second motor protrudes from the drive system, thereby improving the package.

[0016] The transmission system may also include a controller. The controller can be configured to switch the transmission to a configuration in which rotational driving force is transmitted between the input shaft and the drive shaft at a first of a plurality of speed ratios. This can be performed by controlling at least one of a first electric motor and an internal combustion engine to control the speed of the input shaft corresponding to the speed of the drive shaft.

[0017] The transmission may include a sliding input element on an input shaft. The transmission may also include a sliding drive element on a drive shaft. At least one of the sliding input element and the sliding drive element may include pawls on its axial surface. These pawls may be configured to axially engage with at least one gear on the respective shaft. This can advantageously provide a transmission system that allows shifting without the need for a synchronizer.

[0018] A sliding input element may include a sliding input gear. The sliding input gear may be drive-connected to an input shaft. The sliding input gear may slide along the input shaft to selectively engage with at least one input gear. At least one input gear may be drive-connected to a drive shaft.

[0019] At least one input gear may include a first input gear and a second input gear. The sliding input gear is slidable between: a first position, in which the sliding input gear engages with the first input gear; a second position, in which the sliding input gear engages with the second input gear; and a neutral position, in which the sliding input gear is neither engaged with the first input gear nor with the second input gear. This can provide an arrangement that allows the sliding input gear to engage with each gear on either side. This can advantageously increase the number of available gears while saving space.

[0020] A sliding drive element may include a sliding drive gear. The sliding drive gear may be drive-connected to a drive shaft. The sliding drive gear may slide along the drive shaft to selectively engage with at least one drive gear. At least one drive gear may be drive-connected to an input shaft.

[0021] At least one drive gear may include a first drive gear and a second drive gear. The sliding drive gear is slidable between: a first position, in which the sliding drive gear engages with the first drive gear; a second position, in which the sliding drive gear engages with the second drive gear; and a neutral position, in which the sliding drive gear is neither engaged with the first drive gear nor the second drive gear. This arrangement allows the sliding drive gear to engage with the gears on each side and advantageously increases the number of available gears while saving space.

[0022] Embodiments of this disclosure also aim to provide a controller for a drivetrain in a straddle-type hybrid vehicle, the controller being configured to perform any or all of the following operations: controlling the power supplied to a first motor configured to drive an input shaft; controlling the power supplied to a second motor configured to drive a drive shaft; controlling the power output of an internal combustion engine configured to drive the input shaft; controlling the transmission to transmit rotational driving force between the input shaft and the drive shaft at multiple speed ratios; and switching the transmission to a configuration that transmits rotational driving force between the input shaft and the drive shaft at a first speed ratio among multiple speed ratios by controlling at least one of the first motor and the internal combustion engine to thereby control the input shaft speed corresponding to the drive shaft speed.

[0023] The controller can be configured to determine the charge level of the drivetrain battery. The controller can be configured to control the power supplied to the first motor and / or the second motor based on the determined charge level. If the charge level is determined to be above a starting threshold, the controller can be configured to supply power from the battery to the second motor. This provides a useful feature by checking if the battery is fully charged before allowing the motorcycle to start.

[0024] The controller can be configured to start the internal combustion engine using the first electric motor. If it is determined that the charge level is below a starting threshold, the controller can be configured to use the internal combustion engine to charge the battery. This provides a function that uses the engine to charge the battery if the charge level is too low to start.

[0025] If the charge level is determined to exceed the regenerative braking threshold, the controller can be configured to discharge the battery by supplying power to the first motor. This provides advantageous behavior, allowing the controller to discharge the battery to accommodate regenerative braking, thereby improving the energy efficiency of the drivetrain. The controller can be configured to determine the regenerative braking threshold based on calculations of the battery's sustained maximum charge recovery. This provides a method for dynamically controlling the battery's maximum permissible charge capacity to maximize regenerative braking and thus improve energy efficiency. The battery's sustained maximum charge recovery can be determined based on a predicted navigation route for the motorcycle. This allows the controller to tailor the battery's charge capacity for a specific journey. For example, for a flat route, if the degree of regenerative braking is determined to be relatively low, the battery can be allowed to charge to a higher level.

[0026] Embodiments of this disclosure also aim to provide a straddle-type hybrid vehicle, the transmission system including any or all of the following features: an internal combustion engine configured to drive an input shaft; a first electric motor configured to drive the input shaft; a second electric motor configured to drive a drive shaft; a transmission configured to transmit rotational driving force between the input shaft and the drive shaft at multiple speed ratios; and a controller; wherein the controller is configured to switch the transmission to a configuration that transmits rotational driving force between the input shaft and the drive shaft at a first speed ratio among multiple speed ratios by controlling at least one of the first electric motor and the internal combustion engine to control the input shaft speed corresponding to the drive shaft speed.

[0027] Embodiments of this disclosure are also intended to provide a straddle-type vehicle including a drivetrain and / or controller as described above herein. Attached Figure Description

[0028] Embodiments of this disclosure will now be described by way of example only with reference to the accompanying drawings, in which: Figure 1 A schematic diagram of a transmission system according to an embodiment of the present disclosure is shown; Figure 2 It shows Figure 1 Another schematic diagram of the transmission system; Figure 3 It shows Figure 1 and Figure 2 A schematic diagram of the transmission system in its first configuration; Figure 4 It shows Figure 1 and Figure 2 A schematic diagram of the transmission system in its second configuration; Figure 5 It shows Figure 1 and Figure 2 A schematic diagram of the transmission system in the third configuration; Figure 6 It shows Figure 1 and Figure 2 A schematic diagram of the transmission system in its fourth configuration; Figure 7 It shows Figure 1 and Figure 2 A schematic diagram of the transmission system in its fifth configuration; Figure 8 It shows the use of Figure 1 and Figure 2 A schematic diagram of the crankcase of the transmission system. Detailed Implementation

[0029] Embodiments of this disclosure relate to a drivetrain for a straddle-type vehicle (e.g., a motorcycle). This disclosure is not limited to straddle-type vehicles, but can more broadly relate to light motor vehicles (i.e., L-class vehicles), such as light two-wheeled motor vehicles (including mopeds), three-wheeled mopeds, two-wheeled motorcycles, two-wheeled motorcycles with sidecars, motorized tricycles, light four-wheeled vehicles, and heavy four-wheeled vehicles. The drivetrain is used in a hybrid electric vehicle employing a P1 and P3 architecture, such that a first electric motor (P1) is connected to an engine, and a second electric motor (P3) is connected to a drive shaft to drive the wheels. The engine and the first electric motor are arranged to drive the input shaft. The drivetrain includes a transmission so that driving force from the input shaft can be transmitted to the drive shaft. Both the first and second electric motors are connected to a battery. The second electric motor can use the battery's power to drive the wheels and can provide regenerative braking capability by acting as a generator to charge the battery during vehicle braking. The first electric motor can act as a generator, utilizing the rotational driving force of the engine to charge the battery.

[0030] In the examples disclosed herein, the transmission system does not have a clutch for separating the engine from the input shaft. Instead, the engine output is always transmitted to the transmission's input shaft. The transmission does not use synchronizers to help engage the gears in the transmission. Instead, the transmission uses sliding elements (e.g., claw couplings) to selectively engage gears to select different gear ratios. In some examples, the transmission has two sliding claws, one on the input shaft and one on the drive shaft. Each sliding claw can slide between different positions to engage gears on either side. If a sliding claw attempts to engage gears operating at significantly different speeds, the engagement can damage the transmission and generate noise. To provide smoother engagement, the transmission system's controller speeds up or slows down the input shaft, reducing or eliminating the relative rotational speeds between the engaged gears. The controller achieves this by increasing or decreasing the power delivered to the first electric motor to adjust the rotational speed of its rotor. Alternatively, or otherwise, the controller can change the input shaft rotational speed by controlling the engine speed (e.g., by controlling ignition and / or throttle opening).

[0031] Figure 1A schematic diagram of a drivetrain 100 for a straddle-type hybrid vehicle is shown. The drivetrain 100 includes an internal combustion engine (ICE) configured to drive an input shaft 102. The drivetrain 100 also includes a first motor 104 configured to drive the input shaft 102 and a second motor 160 configured to drive a drive shaft 171. The drivetrain 100 also includes a transmission 103 configured to transmit rotational drive force between the input shaft 102 and the drive shaft 171 at multiple speed ratios. A controller 180 of the drivetrain 100 is configured to switch the transmission 103 to a configuration that transmits rotational drive force between the input shaft 102 and the drive shaft 171 at a first of multiple speed ratios by controlling at least one of the first motor 104 and the ICE 105 to control the speed of the input shaft 102 corresponding to the speed of the drive shaft 171.

[0032] The drivetrain 100 provides a P1 / P3 hybrid drive architecture. Specifically, the first motor 104 provides a P1 motor / generator, and the second motor 160 provides a P3 motor / generator. In this respect, the drivetrain 100 also includes a battery 165 electrically connected to the first motor 104 and the second motor 160. The first motor 104 can drive the input shaft 102 by being driven through it. Driven through the input shaft 102, this means that rotation of the first motor 104 (particularly its rotor) causes rotation of the input shaft 102, and vice versa. It is understood that these two components do not need to be directly connected to each other to achieve this rotation. The ICE 105 can be configured to drive the input shaft 102 by the action of a reciprocating piston (not shown) on the crankshaft. Therefore, both the first motor 104 and the ICE 105 are configured to drive and be driven by the input shaft 102. Therefore, the first motor 104 can be configured as an integrated starter generator (ISG) for the ICE 105.

[0033] The second motor 160 can be configured to drive the drive shaft 171 via a driveshaft 171. Driven connection to the drive shaft 171 means that rotation of the second motor 160 (particularly its rotor) causes rotation of the drive shaft 171, and vice versa. Similarly, these components do not need to be directly connected to achieve this rotation, but can be connected via one or more gear pairs. The drive shaft 171 is configured to transmit rotational driving force between the drivetrain 100 and the wheels 175 of the straddle-type vehicle. Therefore, the second motor 160 can be considered a traction motor.

[0034] The transmission 103 can use multiple gears to transmit rotational driving force between the input shaft 102 and the drive shaft 171, each gear being driveably connected to either the input shaft 102 or the drive shaft 171. In this respect, the transmission 103 has multiple configurations to select whether and to what extent rotational driving force is transmitted between the input shaft 102 and the drive shaft 171. In neutral configuration, the transmission 103 prevents the transmission of rotational driving force. In another configuration, the transmission 103 allows the transmission of rotational driving force at a first gear ratio. This is facilitated by engaging a first gear driveably connected to the input shaft 102 and a second gear driveably connected to the drive shaft 171. In other configurations, the transmission 103 allows the transmission of rotational driving force at gear ratios other than the first gear ratio. The transmission 103 can be controlled by a controller 180 to switch between different configurations.

[0035] The drivetrain 100 is a clutchless drivetrain because there is no clutch mechanism to selectively disengage the ICE 105 from the input shaft 102. For example, the drivetrain 100 can be arranged such that the rotational drive transmission between the input shaft 102 and the ICE 105 is uninterrupted. Furthermore, the drivetrain 100 does not use synchronizers in the transmission 103 to assist gear changing. Instead, to engage the first gear with the second gear (e.g.), the controller 180 is configured to match the speeds of the first and second gears by controlling the speed of the input shaft 102 via the first motor 104. In one case, if the first gear rotates at a slower speed than the second gear, the controller can supply more power to the first motor 104, causing the first motor 104 to provide more rotational drive force to the input shaft 102, thereby accelerating the input shaft to a speed corresponding to the drive shaft 171. The corresponding speed does not necessarily require the speed of the input shaft 102 to be the same as or similar to the speed of the drive shaft 171. Conversely, the controller 180 controls the speed of the input shaft 102 so that the engaged gears have a matching or near-matching rotational speed (i.e., revolutions per minute).

[0036] The drivetrain 100 facilitates multiple operating modes in a hybrid motorized vehicle. In Electric Vehicle (EV) mode, the second motor 160 can use electricity from the battery 165 to drive the wheels 175 via the drive shaft 171. This mode may be particularly suitable for vehicle start-up (i.e., acceleration from zero) and low-speed driving. Simultaneously, the ICE 105 can be used to drive the input shaft 102 to charge the battery 165 via the first motor 104, which acts as a generator. Therefore, this mode does not require any rotational drive force to be transmitted between the drive shaft 171 and the input shaft 102, allowing the transmission 103 to be in neutral.

[0037] In hybrid mode, the second motor 160 can continue to drive the drive shaft 171 using electricity from the battery 165, supplemented by torque provided by the ICE 105. This mode may be particularly suitable for vehicle acceleration at higher speeds. In this mode, the transmission 103 is controlled to transmit rotational drive force from the input shaft 102 to the drive shaft 171. Simultaneously, the first motor 104 can operate in generator mode, charging the battery 165 via rotational drive of the input shaft 102.

[0038] In stationary charging mode, the ICE 105 can provide rotational drive force to the input shaft 102 to charge the battery 165 via the first motor 104 operating in generator mode. In this mode, the transmission 103 can be in neutral to prevent any rotational drive force from being transmitted to the drive shaft 171 during charging. This mode may be particularly suitable for low battery situations, where there is enough battery to use the first motor 104 as a starter motor to start the ICE 105, but not enough battery to sustain driving in EV mode.

[0039] In ICE mode, ICE 105 can provide rotational driving force to wheels 175 via input shaft 102 and drive shaft 171. In this mode, transmission 103 is in a coupled configuration and second motor 160 is not operating, so the vehicle is driven entirely by ICE 105.

[0040] Controller 180 can be configured to determine the charge level of battery 165. Therefore, controller 180 can be configured to control the power supplied to the first motor 104 and / or the second motor 160 based on the determined charge level. For example, controller 180 can determine that the charge level is above a start-up threshold, so controller 180 can supply power to the second motor 160 to provide torque to wheel 175. In another example, controller 180 can determine that the charge level is below a start-up threshold, so battery 165 cannot provide sufficient power to the second motor 160 for starting. In this case, controller 180 can be configured to use the first motor 104 as a starter motor to start ICE 105, and then use ICE 105 to charge battery 165 by using the first motor 104 as a generator until the charge level is sufficient for starting using the second motor 160.

[0041] In some situations, the charge level of battery 165 may be too high to accommodate regenerative braking. If it is determined that the charge level exceeds the regenerative braking threshold, controller 180 can discharge battery 165 by supplying power from battery 165 to first motor 104. The regenerative braking threshold can be determined based on a calculation of the maximum sustained charge recovery of battery 165. In other words, controller 180 can determine the maximum charge recovery for a single braking event and use that maximum charge recovery to influence the regenerative braking threshold. The maximum sustained charge recovery can be determined based on the vehicle's predicted navigation route. For example, if controller 180 determines that the vehicle may encounter a steep downhill slope requiring significant braking, it can lower the regenerative braking threshold to accommodate the charge recovery during the downhill section.

[0042] Figure 2 It shows about Figure 1 A schematic diagram illustrating additional details of the described transmission system 100. (ICE 105 is not shown in the diagram.) Figure 2 The crankshaft 101 is not shown in the diagram, but is schematically represented by the crankshaft 101. In addition to the crankshaft 101 driven by the reciprocating motion of the piston of the ICE 105, a first motor 104 is also configured to drive the crankshaft 101. In this respect, the first motor 104 (particularly its rotor) is driveably connected to the crankshaft 101. The first motor 104 may be directly connected to the crankshaft 101 or form an integral part of the crankshaft 101. The crankshaft 101 is driveably connected to the input shaft 102 via a main drive 109. For example, the crankshaft 101 may be connected to the input shaft 102 via a gear pair provided by the main drive 109. The axis of rotation of the crankshaft 101 is parallel to the axis of rotation of the input shaft 102.

[0043] A second motor 160 may be configured to drive an intermediate shaft 161. In this arrangement, the second motor 160 (particularly its rotor) is driveably connected to the intermediate shaft 161. The second motor 160 may be directly connected to the intermediate shaft 161 or form an integral part of the intermediate shaft 161. The axis of rotation of the intermediate shaft 161 is parallel to the axes of rotation of the crankshaft 101 and the input shaft 102. At least a portion of the intermediate shaft 161 is concentrically housed within the input shaft 102. Therefore, the axes of rotation of the intermediate shaft 161 and the input shaft 102 are collinear. In the example shown, the first motor 160 is located at a first axial end of the input shaft 102, and the intermediate shaft 161 extends through the input shaft 102 and protrudes from a second axial end of the input shaft.

[0044] As described above, drive shaft 171 is drive-connected to wheel 175. In the illustrated arrangement, the connection is provided by chain drive 173. Chain drive 173 connects between transmission sprocket 172 and wheel sprocket 174 to transmit rotational driving force between transmission sprocket 172 and wheel sprocket 174. Transmission sprocket 172 is drive-connected to drive shaft 171 or is an integral part thereof.

[0045] The transmission 103 includes multiple gear pairs. In the illustrated arrangement, the transmission 103 includes five gear pairs. A first gear pair 110 is configured to transmit rotational driving force from an intermediate shaft 161 to a drive shaft 171, such that a second motor 160 can be drively connected to the drive shaft 171. A second gear pair 120 is configured to selectively transmit rotational driving force from an input shaft 102 to the drive shaft 171, depending on the configuration of the transmission 103. The second gear pair 120 includes an input gear disposed around the input shaft 102 and a drive gear disposed around the drive shaft. The third gear pair 130, the fourth gear pair 140, and the fifth gear pair 150 can be arranged in a similar manner to the second gear pair 120, except that the gear ratio between the drive gear and the input gear decreases for each successive gear pair.

[0046] Figure 3 This is a schematic diagram of a transmission system 100 showing a detailed example of a transmission 103. (Compared to...) Figure 2 Similarly, the transmission system 100 is configured such that the first motor 104 and the ICE (not shown) are configured to drive the input shaft 102, which can be done via the crankshaft 101 and the main drive 109. The second motor 160 is configured to drive the drive shaft 171 via an intermediate shaft 161, which is driveably connected to the final drive or transmission sprocket 172. In the illustrated arrangement, the input shaft 102 is fitted over the intermediate shaft 161.

[0047] The transmission 103 includes five gear pairs. (As in...) Figure 2 As described above, the first gear pair 110 may be disposed at the end of the intermediate shaft 161 opposite to the second motor 160. In an alternative arrangement, the first gear pair 110 may be disposed adjacent to the second motor 160, for example, between the second motor 160 and the main drive 109. The first gear pair 110 drives the second motor 160 to the drive shaft 171. In this way, the second motor 160 is permanently connected to the drive shaft 171, such that the rotational driving force or torque provided by the second motor 160 will always be transmitted to the drive shaft 171, and similarly, the rotational driving force or torque provided by the drive shaft 171 will always be transmitted to the second motor 160.

[0048] The first gear pair 110 may include a first input gear 111 and a first drive gear 115. The first input gear 111 is fixed to an intermediate shaft 161 for rotation with the intermediate shaft 161. In other arrangements, the first input gear 111 may be an integral part of the intermediate shaft 161, as the first input gear 111 may be provided by a plurality of teeth extending radially from the intermediate shaft 161. This applies to any gear described as fixed to a shaft. The first drive gear 115 is fixed to a drive shaft 161 for rotation with the drive shaft. The first drive gear 115 is drive-connected to the first input gear 111, for example, by meshing with the first input gear 111 such that torque is transmitted between the first drive gear 115 and the first input gear 111.

[0049] The second gear pair 120 may be disposed at the proximal end of the input shaft 102 and the drive shaft 171, which may be the end closest to the second motor 160. In the illustrated arrangement, the second gear pair 120 is arranged such that the main drive 109 is axially positioned between the second gear pair 120 and the second motor 160. The second gear pair 120 may include a second input gear 121 and a second drive gear 125. The second input gear 121 is fixed to the input shaft 102 to rotate with the input shaft 102. The second drive gear 125 is rotatably connected to the drive shaft 171 such that the second drive gear 125 can rotate independently of the drive shaft 171. The second drive gear 125 is mounted at a fixed axial position on the drive shaft 171. The second drive gear 125 is drive-connected to the second input gear 121, for example by meshing with the second input gear 121, such that torque is transmitted between the second drive gear 125 and the second input gear 121.

[0050] The third gear pair 130 may be disposed adjacent to the second gear pair 120. Specifically, the third gear pair 130 may be disposed between the second gear pair 120 and the fifth gear pair 150. The third gear pair 130 may include a third input gear 131 and a sliding drive gear 135, which may be a sliding pawl. The third input gear 131 is rotatably connected to the input shaft 102, such that the third input gear 131 can rotate independently of the input shaft 102. The third input gear 131 is mounted at a fixed axial position on the input shaft 102. The sliding drive gear 135 is mounted on the drive shaft 171 to rotate with the drive shaft 171 and can slide along the drive shaft 171. Thus, although the third input gear 131 has a fixed axial position along the input shaft 102, the sliding drive gear 135 can slide relative to the drive shaft 171 and the third input gear 131. The sliding drive gear 135 is configured to slide in a first direction toward the second gear pair 120 and in a second direction toward the fifth gear pair 150, which will combine Figure 4 and Figure 7To explain in more detail: The sliding drive gear 135 is driven by the third input gear 131, for example by meshing with the third input gear 131, so that torque is transmitted between the sliding drive gear 135 and the third input gear 131.

[0051] A fourth gear pair 140 may be disposed adjacent to the first gear pair 110. Specifically, the fourth gear pair 140 may be disposed at the distal end of the input shaft 102, between the first gear pair 110 and the fifth gear pair 150. The fourth gear pair 140 may include a fourth input gear 141 and a fourth drive gear 145. In the illustrated example, the fourth input gear 141 is rotatably connected to the input shaft 102 such that the fourth input gear 141 can rotate independently of the input shaft 102. The fourth input gear 141 is mounted at a fixed axial position on the input shaft 102. The fourth drive gear 145 is fixed to the drive shaft 171 to rotate with the drive shaft 171. The fourth drive gear 145 is drively connected to the fourth input gear 141, for example, by meshing with the fourth input gear 141, such that torque is transmitted between the fourth drive gear 145 and the fourth input gear 141.

[0052] A fifth gear pair 150 may be disposed between the third gear pair 130 and the fourth gear pair 140. The fifth gear pair 150 may include a fifth drive gear 155 and a sliding input gear 151, which may be a sliding pawl. The fifth drive gear 155 is rotatably connected to the drive shaft 171, allowing it to rotate independently of the drive shaft 171. The fifth drive gear 155 is mounted at a fixed axial position on the drive shaft 171. The sliding input gear 151 is mounted on the input shaft 102 to rotate with and slide along the input shaft 102. In this way, while the fifth drive gear 155 has a fixed axial position along the drive shaft 171, the sliding input gear 151 can slide relative to the input shaft 102 and the fifth drive gear 155. The sliding input gear 151 is configured to slide in a first direction toward the third gear pair 130 and in a second direction toward the fourth gear pair 140, which will... Figure 5 and Figure 6 The following explains this in more detail. The sliding input gear 151 is driven by the fifth drive gear 155, for example, by meshing with the fifth drive gear 155, so that torque is transmitted between the sliding input gear 151 and the fifth drive gear 155.

[0053] Figure 3A first configuration of the transmission 103 is shown, in which no rotational driving force is transmitted between the input shaft 102 and the drive shaft 171. In operation, assuming the main drive 109 is driven by the ICE 105, the second input gear 121 and the second drive gear 125 are driven by the input shaft 102. Since the second drive gear 125 is not drive-connected to the drive shaft 171, no torque is transmitted to the drive shaft 171. Similarly, the sliding input gear 151 and the fifth drive gear 155 rotate with the input shaft 102, but no torque is transmitted to the drive shaft 171 because the fifth drive gear 155 is not drive-connected to the drive shaft 171. For the third gear pair 130, the third input gear 131 is not drive-connected to the input shaft 102, so no torque is transmitted between the input shaft 102 and the third input gear 131. Similarly, for the fourth gear pair 140, the fourth input gear 141 is not drive-connected to the input shaft 102, so no torque is transmitted between the input shaft 102 and the fourth input gear 141. In the first configuration, torque can be transmitted between the second motor 160 and the drive shaft 171 via the first gear pair 110. Therefore, the second motor 160 can provide prime mover power to the transmission sprocket 172 in EV drive mode. In regenerative braking mode, the rotational driving force transmitted from the wheel 175 via the transmission sprocket 172 is transmitted to the second motor 160 via the first gear pair 110, so that the second motor 160, operating as a generator, can charge the battery.

[0054] Figure 4A second configuration of the transmission 103 is shown. As described above, the sliding drive gear 135 is slidable toward the second gear pair 120 in a first direction (indicated by the arrow), more specifically toward the second drive gear 125. The sliding drive gear 135 is configured to engage with the second drive gear 125 to rotate at the same speed as the second drive gear 125. In this way, the sliding drive gear 135 is driveably connected to the second drive gear 125, such that torque can be transmitted between the sliding drive gear 135 and the second drive gear 125 upon engagement. This engagement between adjacent gears can be provided by any means suitable for transmitting torque between axially opposed gears. In the arrangement described herein, engagement is provided by a claw coupling. In this respect, the second drive gear 125 includes a second drive gear claw 126, and the sliding drive gear 135 includes a first sliding drive claw 136. The second drive gear claw 126 and the first sliding drive claw 136 are provided on their respective gears as axial protrusions and recesses distributed about the axis of rotation of the drive shaft 171. The transmission 103 is arranged such that the second drive gear pawl 126 and the first sliding drive pawl 136 face each other. In this way, when the sliding drive gear 135 moves toward the second gear pair 120, the second drive gear pawl 126 and the first sliding drive pawl 136 engage with each other, allowing torque to be transmitted between the sliding drive gear 135 and the second drive gear 125. Therefore, rotational driving force can be transmitted between the input shaft 102 and the drive shaft 171 via the second gear pair 120 and the sliding drive gear 135.

[0055] Figure 5A third configuration of the transmission 103 is shown. As described above, the sliding input gear 151 is slidable toward the third gear pair 130 in a first direction (indicated by the arrow), more specifically toward the third input gear 131. The sliding input gear 151 is configured to engage with the third input gear 131 so as to rotate at the same rotational speed as the third input gear 131. In this way, the sliding input gear 151 is driveably connected to the third input gear 131, such that torque can be transmitted between the sliding input gear 151 and the third input gear 131 upon engagement. Engagement may be provided by a claw connector. In the illustrated arrangement, the third input gear 131 includes a third input gear claw 132, and the sliding input gear 151 includes a first sliding input claw 152. The third input gear claw 132 and the first sliding input claw 152 are provided on their respective gears as axial protrusions and recesses distributed about the axis of rotation of the input shaft 102. The transmission 103 is arranged such that the third input gear claw 132 and the first sliding input claw 152 face each other. In this way, when the sliding input gear 151 moves toward the third gear pair 130, the third input gear pawl 132 and the first sliding input pawl 152 engage with each other, so that torque is transmitted between the sliding input gear 151 and the third input gear 131. Therefore, rotational driving force can be transmitted between the input shaft 102 and the drive shaft 171 via the third gear pair 130 and the sliding input gear 151.

[0056] Figure 6 A fourth configuration of the transmission 103 is shown. As described above, the sliding input gear 151 is slidable toward the fourth gear pair 140 in a second direction (indicated by the arrow), more specifically toward the fourth input gear 141. The sliding input gear 151 is configured to engage with the fourth input gear 141 to rotate at the same speed as the fourth input gear 141. In this way, the sliding input gear 151 is driveably connected to the fourth input gear 141, such that torque can be transmitted between the sliding input gear 151 and the fourth input gear 141 upon engagement. Engagement can be provided by a claw connector. In the illustrated arrangement, the fourth input gear 141 includes a fourth input gear claw 142, and the sliding input gear 151 includes a second sliding input claw 153. The fourth input gear claw 142 and the second sliding input claw 153 are provided on their respective gears as axial protrusions and recesses distributed about the axis of rotation of the input shaft 102. The transmission 103 is arranged such that the fourth input gear claw 142 and the second sliding input claw 153 face each other. In this way, when the sliding input gear 151 moves toward the fourth gear pair 140, the fourth input gear pawl 142 and the second sliding input pawl 153 engage with each other, thereby transmitting torque between the sliding input gear 151 and the fourth input gear 141. Therefore, rotational driving force can be transmitted between the input shaft 102 and the drive shaft 171 via the fourth gear pair 140 and the sliding input gear 151.

[0057] Figure 7 A fifth configuration of the transmission 103 is shown. As described above, the sliding drive gear 135 is slidable toward the fifth gear pair 150, more specifically toward the fifth drive gear 155, in a second direction (indicated by the arrow). The sliding drive gear 135 is configured to engage with the fifth drive gear 155 to rotate at the same speed as the fifth drive gear 155. In this way, the sliding drive gear 135 is driveably connected to the fifth drive gear 155, such that torque can be transmitted between the sliding drive gear 135 and the fifth drive gear 155 upon engagement. Engagement can be provided by a claw connector. In the illustrated arrangement, the fifth drive gear 155 includes a fifth drive gear claw 156, and the sliding drive gear 135 includes a second sliding drive claw 137. The fifth drive gear claw 156 and the second sliding drive claw 137 are provided on their respective gears as axial protrusions and recesses distributed about the axis of rotation of the input shaft 102. The transmission 103 is arranged such that the fifth drive gear claw 156 and the second sliding drive claw 137 face each other. In this way, when the sliding drive gear 135 moves toward the fifth gear pair 150, the fifth drive gear pawl 156 and the second sliding drive pawl 137 engage with each other, thereby transmitting torque between the sliding drive gear 135 and the fifth drive gear 155. Therefore, rotational driving force can be transmitted between the input shaft 102 and the drive shaft 171 via the fifth gear pair 150 and the sliding drive gear 135.

[0058] Reference Figures 3 to 7 The transmission 103 generally comprises five gear pairs, including two sliding gears. The first gear pair 110 drives the second motor 160 to the drive shaft 171. The input shaft 102 may be driven to the drive shaft 171 by one of the remaining gear pairs and a sliding gear (e.g., a sliding input gear 151 or a sliding drive gear 135).

[0059] A sliding input gear 151 is slidable along the input shaft 102 for selective engagement with a third input gear 131 and a fourth input gear 141. In this regard, the sliding input gear 151 has a first position and a second position. In the first position, the sliding input gear 151 engages with the third input gear 131, which is driven to the drive shaft 171 via a sliding drive gear 135. In the second position, the sliding input gear 151 engages with the fourth input gear 141, which is driven to the drive shaft 171 via a fourth drive gear 145. The sliding input gear 151 also has a neutral position, in which it is neither engaged with the third input gear 131 nor with the fourth input gear 141.

[0060] A sliding drive gear 135 is slidable along the drive shaft 171 for selective engagement with a second drive gear 125 and a fifth drive gear 155. In this regard, the sliding drive gear 135 has a first position and a second position. In the first position, the sliding drive gear 135 engages with the second drive gear 125, which is driveably connected to the input shaft 102 via a second input gear 121. In the second position, the sliding drive gear 135 engages with the fifth drive gear 155, which is driveably connected to the input shaft 102 via a sliding input gear 151. The sliding drive gear 135 also has a neutral position, in which it neither engages with the second drive gear 125 nor the fifth drive gear 155.

[0061] The transmission 103 may employ a sequential drive system. This means that the transmission 103 can be configured to allow selection of only the next or previous gear in the gear sequence. For example, in first gear, the transmission may only allow shifting to second gear. In second gear, the transmission may only allow shifting to first or third gear, and so on. In some arrangements, the movement of the sliding input gear 151 and the sliding drive gear 135 may be controlled by a shift drum mechanism (not shown) of the transmission. Such a shift drum mechanism may include a selection drum with two tracks (one for each sliding gear 151, 135) that guide the path of the selection fork connected to each sliding gear 151, 135, thereby controlling the position of these sliding gears along their respective shafts. A controller 180 is configured to control the rotation of the shift drum to select a gear as needed. The controller 180 may automatically and / or in response to a driver's command (such as via a button on the handlebars of a straddle-mounted vehicle) actuate the rotation of the shift drum.

[0062] The operation of the transmission system 100 of a vehicle undergoing acceleration will now be described. Starting from a stationary vehicle, a second motor 160 is used as a traction motor to perform a start-up, while the sliding gear remains in its neutral position. To provide additional torque from the main drive 109 at higher speeds, the transmission 103 is shifted to a second configuration by moving the sliding drive gear 135 to engage with the second drive gear 125, thereby facilitating the transmission of torque from the input shaft 102 to the drive shaft 171 via the second gear pair 120. Before the shift, the sliding drive gear 135 may have a significantly different rotational speed than the second drive gear 125, such that engagement could result in damage or unwanted noise. To match the rotational speed of the sliding drive gear 135 with that of the second drive gear 125, the controller 180 controls the torque output of the first motor 104 to control the speed of the second drive gear 125 to correspond to the speed of the sliding drive gear 135. The controller 180 can determine the rotational speed of the sliding drive gear 135 based on the rotational speed of the drive shaft 171. Similarly, the controller 180 can determine the rotational speed of the second drive gear 125 based on the rotational speed of the input shaft 102 or the crankshaft 101. Therefore, typically, the controller 180 controls the torque provided by the first motor 104 to control the rotational speed of the input shaft 102 corresponding to the rotational speed of the drive shaft 171. It can be understood that shifting to the third, fourth, and fifth configurations can be implemented in a corresponding manner.

[0063] The controller 180 can also be configured to facilitate appropriate gear shifting during a hard braking event. For example, if the transmission is in fifth configuration during a hard braking event ( Figure 7 The controller 180 can be configured to move the transmission 103 to neutral by disengaging the sliding drive gear 135 from the fifth drive gear 155, thereby disconnecting the ICE 105 from the drive shaft 171. The drive shaft 171 can then continue to drive the second motor 160 for regenerative braking. The controller 180 can shut down the ICE 105 and shift gears in the following pattern: neutral to fourth gear to neutral to third gear to neutral to second gear to neutral. In each case, the first motor 104 can be used to synchronize the speed of the input shaft 102 with that of the drive shaft 171 before engaging the axially opposite gears. Once hard braking is complete, the vehicle can be driven using the second motor 160 in the first configuration, and upshifts can then be performed in the normal manner as described above. Downshifts can also be performed when the vehicle is stopped. The first motor 104 can be slightly rotated with the input shaft 102 to allow engagement of the claw coupling. This rotation can be performed with very low torque to prevent the wheels from moving via the drive shaft 171.

[0064] Figure 8A crankcase 106 of the transmission system 100 is shown. The crankcase 106 provides a housing for the crankshaft 101, input shaft 102, and drive shaft 171. Thus, the crankcase 106 accommodates both the crankshaft 101 of the ICE 105 and the transmission. The crankcase 106 may be formed from a single monolithic material (e.g., a single casting), or it may be formed from two or more components, each of which may be a single casting and these components may be connected together via studs, screws, or similar fastening devices. In the arrangement shown, the transmission includes an intermediate shaft 161, which is also accommodated within the crankcase 106.

[0065] like Figure 8 As shown, the ICE 105 may be at least partially housed in the crankcase 106. Specifically, the crankcase 106 may include at least one opening configured to receive at least one piston of the ICE 105, facilitating connection of the at least one piston to the crankshaft 101 within the crankcase 106. The crankcase 106 may at least partially house a first motor 104. For example, the crankcase 106 may include an opening configured to receive a rotary drive element of the first motor 104 for connection to the crankshaft 101. The crankcase 106 may at least partially house a second motor 160. Specifically, the crankcase 106 may include an opening configured to receive a rotary drive element of the second motor 160 for connection to a drive shaft 171, for example, via an intermediate shaft 161. In each case, the rotary drive element may be the rotor of the respective motor, or a component driveably connected to the rotor.

[0066] The transmission system 100 can be arranged such that the first motor 104 is located on the crankcase 106 opposite to the second motor 160. Furthermore, the ICE 105 can be arranged on the crankcase 106 opposite to the drive shaft 171. The crankshaft 101, input shaft 102, and drive shaft 171 can be arranged such that their axes of rotation occupy a triangular array. Figure 8 As shown, the rotation axes of these shafts (including the intermediate shaft 161 coaxial with the input shaft 102) are arranged in the crankcase 106 such that the rotation axes of these shafts are located at the independent vertices of an imaginary triangle 107, which is perpendicular to the rotation axes.

[0067] The crankshaft 101, input shaft 102, drive shaft 171, and optional intermediate shaft 161 can be arranged in parallel. In the arrangement shown, the crankshaft 101 is arranged such that its axis of rotation is parallel to and spaced apart from the axes of rotation of the input shaft 102, drive shaft 171, and intermediate shaft 161. The crankshaft 101 may be spaced apart from these shafts in a direction perpendicular to its axis of rotation. The drive shaft 171 is arranged such that its axis of rotation is parallel to and spaced apart from the crankshaft 101, input shaft 102, and intermediate shaft 161 (e.g., in the vertical direction). Therefore, in the arrangement shown, the crankshaft 101 does not share a common axis of rotation with any shaft of the transmission (e.g., input shaft 102 and drive shaft 171).

[0068] Although they have already combined Figures 3 to 7 The transmission is described as including a sliding input gear 151 and a sliding drive gear 135, but an alternative arrangement (not shown) may instead employ a sliding pawl. In such an arrangement, at least one of the input shaft 102 and drive shaft 171 may include a sliding element configured to slide between a first gear and a second gear on the respective shaft for selective engagement with either the first or second gear. The sliding element may be a toothless pawl, and both the first and second gears may rotate independently on the respective shafts, for example, by fitting onto the respective shafts.

[0069] Reference Figure 3 The above arrangement is conceivable. The sliding input gear 151 is not driveably connected to the input shaft 102 and can slide along the input shaft 102, but rather can be positioned in a fixed position along the input shaft 102 and fitted onto the input shaft 102 for independent rotation. A sliding pawl ring, which may have teeth on each of its axial planes, can be provided between two gears (e.g., gears 131 and 151) on the input shaft 102. In this way, the sliding pawl ring can selectively engage gears 131 and 151 to transmit driving force between the input shaft 102 and the drive shaft 171 via the selected gear. Further modifications are conceivable by providing such a sliding pawl ring between gears 141 and 151. Figure 3 The layout shown. Similarly, it can be modified. Figure 3 A gear is arranged around the drive shaft 171, specifically a sliding drive gear 135 is positioned at a fixed position along the drive shaft 171 and is fitted onto the drive shaft 171 to rotate independently. A sliding pawl ring can then be placed between gears 125 and 135, and another sliding pawl ring can be placed between gears 135 and 155.

[0070] In view of the foregoing, this disclosure is not limited to the sliding element being a gear. Instead, the sliding element does not need to have teeth, but can be replaced by a sliding claw ring. It is understood that, in combination with... Figures 4 to 7All the gear combinations outlined can also be achieved by using sliding claw rings between each pair of axially engaging gears.

[0071] As can be understood from the foregoing description, many features of the different examples are interchangeable and composable. This disclosure extends to further examples covering combinations of features not specifically mentioned in the different examples. In fact, many features are presented in the foregoing examples, and those skilled in the art will understand that these features can be advantageously combined with each other.

Claims

1. A drivetrain for a motorcycle-style hybrid vehicle, the drivetrain comprising: An internal combustion engine, the internal combustion engine including a crankshaft; A first motor, configured to drive the crankshaft; An input shaft, which is connected to the crankshaft drive; The second motor is connected to the drive shaft via a transmission connection. as well as A transmission configured to transmit rotational driving force between the input shaft and the drive shaft at multiple speed ratios.

2. The transmission system according to claim 1, wherein, The rotor of the first motor is directly connected to the crankshaft.

3. The transmission system according to claim 1 or 2, wherein, The crankshaft, the input shaft, and the drive shaft are integrated within the crankcase.

4. The transmission system according to claim 3, wherein, The crankcase includes at least one opening, said at least one opening being configured to receive at least one of the following: The piston shaft of the internal combustion engine; The rotation drive element of the first motor; and The rotation drive element of the second motor.

5. The transmission system according to any of the preceding claims, wherein, The crankshaft is adjacent to at least one of the input shaft and the drive shaft in a direction perpendicular to the axis of rotation of the crankshaft.

6. The transmission system according to any of the preceding claims, wherein, The rotation axis of the crankshaft is collinear with the rotation axis of the first motor.

7. The transmission system according to any of the preceding claims, wherein, The rotation axes of the crankshaft, the input shaft, and the drive shaft are parallel and arranged in a triangular array.

8. The transmission system according to any of the preceding claims, wherein, The second motor is connected to the drive shaft via an intermediate shaft.

9. The transmission system according to claim 8, wherein, The intermediate shaft is collinear with the input shaft.

10. The transmission system according to claim 8 or 9, wherein, The intermediate shaft is concentrically arranged within the input shaft.

11. The transmission system according to any one of claims 8 to 10, wherein, The intermediate shaft is connected to the drive shaft via a gear located at the end of the intermediate shaft opposite to the second motor.

12. The transmission system according to any of the preceding claims, further comprising a controller configured to switch the transmission to a configuration that transmits rotational driving force between the input shaft and the drive shaft at a first of the plurality of speed ratios by controlling at least one of the first motor and the internal combustion engine to control the rotational speed of the input shaft corresponding to the rotational speed of the drive shaft.

13. The transmission system according to any of the preceding claims, wherein, The transmission includes a sliding input element on the input shaft and a sliding drive element on the drive shaft.

14. The transmission system according to claim 13, wherein, At least one of the sliding input element and the sliding drive element includes a claw on its axial surface, the claw being configured to engage axially with at least one gear on a corresponding shaft.

15. The transmission system according to claim 13 or 14, wherein, The sliding input element includes a sliding input gear that is driven to the input shaft. The sliding input gear is slidable along the input shaft for selective engagement with at least one input gear that is driven to the drive shaft.

16. The transmission system according to claim 15, wherein, The at least one input gear includes a first input gear and a second input gear, and the sliding input gear is slidable between the following positions: In the first position, the sliding input gear engages with the first input gear; In the second position, the sliding input gear engages with the second input gear; as well as In the neutral position, the sliding input gear is neither engaged with the first input gear nor with the second input gear.

17. The transmission system according to any one of claims 13 to 16, wherein, The sliding drive element includes a sliding drive gear that is driven to the drive shaft. The sliding drive gear is slidable along the drive shaft for selective engagement with at least one drive gear that is driven to the input shaft.

18. The transmission system according to claim 17, wherein, The at least one drive gear includes a first drive gear and a second drive gear, and the sliding drive gear is slidable between the following positions: In the first position, the sliding drive gear engages with the first drive gear; In the second position, the sliding drive gear engages with the second drive gear; as well as In the neutral position, the sliding drive gear is neither engaged with the first drive gear nor with the second drive gear.

19. A controller for a drivetrain system of a motorcycle-type hybrid vehicle, the controller being configured to: Control the power supplied to the first motor, which is configured to drive the input shaft; Control the power supplied to the second motor, which is configured to drive the drive shaft; Controlling the power output of an internal combustion engine, the internal combustion engine being configured to drive the input shaft; The transmission is controlled to transmit rotational driving force between the input shaft and the drive shaft at multiple speed ratios; as well as By controlling at least one of the first motor and the internal combustion engine to control the rotational speed of the input shaft corresponding to the rotational speed of the drive shaft, the transmission is configured to transmit rotational driving force between the input shaft and the drive shaft at a first of the multiple speed ratios.

20. The controller according to claim 19, wherein, The controller is configured to: Determine the charge level of the battery in the transmission system; and The power supplied to the first motor and / or the second motor is controlled based on the determined charging level.

21. The controller according to claim 20, wherein, The controller is configured to: If it is determined that the charging level is higher than the starting threshold, then the power of the battery is supplied to the second motor; The internal combustion engine is started using the first motor; and If it is determined that the charging level is below the starting threshold, the internal combustion engine is used to charge the battery.

22. The controller according to claim 20 or 21, wherein, If it is determined that the charging level exceeds the regenerative braking threshold, the controller is configured to discharge the battery by supplying power from the battery to the first motor.

23. The controller according to claim 22, wherein, The controller is configured to determine the regenerative braking threshold based on a calculation of the battery’s continuous maximum charge recovery, wherein the continuous maximum charge recovery of the battery is determined based on a predicted navigation route of the motorcycle.

24. A drivetrain for a straddle-type hybrid vehicle, the drivetrain comprising: An internal combustion engine, configured to drive an input shaft, A first motor, configured to drive the input shaft; A second motor, configured to drive a drive shaft; A transmission configured to transmit rotational driving force between the input shaft and the drive shaft at multiple speed ratios; as well as Controller; The controller is configured to control at least one of the first motor and the internal combustion engine to control the rotational speed of the input shaft relative to the rotational speed of the drive shaft, thereby enabling the transmission to switch to a configuration that transmits rotational driving force between the input shaft and the drive shaft at a first of the multiple speed ratios.

25. A straddle-type vehicle comprising a drivetrain according to any one of claims 1 to 18 or claim 24 and / or a controller according to any one of claims 19 to 23.

Images