Parking brake for electric vehicles with multi-speed transmissions

Abstract

A commercial vehicle comprising at least one driven axle, at least one service brake, at least one propulsion engine and a pair of wheels, wherein the parking brake function of the vehicle is achieved by a bistable locking means acting on both wheels, and wherein at least one multi-speed transmission is provided for simultaneously operating a first drive stage and a second drive stage having a ratio different from that of the first drive stage.

Description

Technical Field

[0001] The present invention relates to a parking brake for an electric vehicle equipped with a multi-stage transmission.

Summary of the Invention

Problems to be Solved by the Invention

[0002] A commercial vehicle can utilize a braking system to which friction is applied so that one or more wheels do not rotate. In some embodiments, the braking system can be implemented using a combined cylinder that includes both a service brake portion and a parking brake portion. The parking brake function can be realized using a spring brake that is axially arranged behind the service brake portion within the combined cylinder housing, in which case it can be a relatively large assembly.

Means for Solving the Problems

[0003] According to an embodiment of the disclosed object, a vehicle drive system for achieving a bistable lock parking brake function is provided. The vehicle drive system includes a first multi-stage transmission including a plurality of driving stages and at least one actuator for operating a first driving stage among the plurality of driving stages. A first actuator of the at least one actuator can operate the first driving stage simultaneously with a second driving stage. The vehicle drive system may further include a second actuator in the at least one actuator to operate the second driving stage simultaneously with the first driving stage actuated by the first actuator. The vehicle drive system may further include a second multi-stage transmission. The second multi-stage transmission may include a plurality of driving stages and third and fourth actuators for operating the first and second driving stages among the plurality of driving stages simultaneously. The vehicle drive system may further include an output shaft lock for mechanically connecting the output of the first multi-stage transmission to the output of the second multi-stage transmission while the first and second driving stages are being operated simultaneously. The actuated second driving stage may be a plurality of driving stages of the first multi-stage transmission or a plurality of driving stages of the second multi-stage transmission. The vehicle drive system may further include an input shaft lock for mechanically connecting the input of the first multi-stage transmission to the input of the second multi-stage transmission when actuated. The vehicle drive system may further include an output shaft lock for mechanically connecting the output of the first multi-stage transmission to the output of the second multi-stage transmission when actuated. The first and second driving stages may have different ratios. The vehicle drive system may further include an auxiliary device for releasing the parking brake function by manually deactivating the first driving stage or the second driving stage. The vehicle drive system may further include a first clutch of the first multi-stage transmission for engaging the first driving stage via the first actuator. The vehicle drive system may further include a second clutch of the first multi-stage transmission for engaging the second driving stage via the second actuator. The vehicle drive system may further include an elastic coupling mechanically connected to the second clutch. The elastic coupling may allow rotation of the input of the first multi-stage transmission to align the first clutch with the first driving stage while the second clutch is engaged with the second driving stage.

[0004] The commercial vehicle comprises at least one driven axle, at least one service brake, at least one propulsion engine and a wheel pair, and the parking brake function of the vehicle is a bistable locking means acting on both wheels The above vehicle drive system that provides It is characterized by being made by. This commercial vehicle may further include a first multi-stage transmission having a first drive stage operated by a first actuator and connected to the first wheel of the wheel pair. This commercial vehicle may further include a second multi-stage transmission having a second drive stage operated by a second actuator and connected to the second wheel of the wheel pair. The parking brake function can be achieved by operating the first drive stage and the second drive stage simultaneously. This commercial vehicle may further include an output shaft lock for connecting the first wheel of the wheel pair to the second wheel of the wheel pair when actuated. This commercial vehicle may further include an input shaft lock for connecting the input of the first multi-stage transmission to the input of the second multi-stage transmission when actuated. The first drive stage may be characterized by having a first ratio different from the second ratio of the second drive stage. This commercial vehicle may further include an elastic coupling and a toothed selector connected to the elastic coupling and a sliding clutch that is limitedly rotatably movable with respect to the sliding shaft of the sliding clutch. The sliding clutch can be actuated by a second actuator. This commercial vehicle may further include a multi-stage transmission having a plurality of drive stages, an actuator, and a sliding clutch that engages the first drive stage and the second drive stage simultaneously when actuated by the actuator. The first drive stage or the second drive stage may include conjugate teeth. The teeth of the toothed selector are formed to mesh with the conjugate teeth when in tooth-to-tooth position. This commercial vehicle may further include an external planetary gear disposed at the outer edge of each wheel of the driven axle. The ratio between the final stage shaft of the differential device driving the wheel pair and the wheel can be greater than 1. This commercial vehicle may further include a manual control unit for actuating the bistable locking means when the commercial vehicle is stopped. This commercial vehicle may further include an electronic brake control unit. The manual control unit may be configured to transmit a brake request to the electronic brake control unit via an electronic signal to actuate the bistable locking means. This commercial vehicle may further include a redundant foot brake module for a redundant brake and a booster.The manual control unit may be configured to send a brake request to the booster via an electronic signal to activate the redundant foot brake module when the electronic brake control unit is unable to execute the brake request.

[0005] Further features, advantages, and embodiments of the disclosed subject matter will be defined or will become apparent from the following detailed description, drawings, and consideration of the claims. Further, it is to be understood that both the foregoing summary and the following detailed description are exemplary and are intended to provide further explanation without limiting the scope of the claims.

[0006] The accompanying drawings, which are included to provide a further understanding of the disclosed subject matter, are incorporated in and constitute a part of this specification. The drawings also show embodiments of the disclosed subject matter and, together with the detailed description, serve to explain the principles of the embodiments of the disclosed subject matter. Features from the illustrated embodiments may be combined, added, removed, and / or otherwise changed as desired without departing from the scope of the disclosed subject matter. The intention is not to show structural details in more detail than may be necessary for a fundamental understanding of the disclosed subject matter and the various ways in which it may be implemented.

Brief Description of the Drawings

[0007]

Figure 1

[0008]

Figure 2A

[0009]

Figure 2B

[0010]

Figure 3

[0011]

Figure 4

[0012]

Figure 5

[0013]

Figure 6

[0014]

Figure 7

[0015]

Figure 8

[0016]

Figure 9

[0017]

Figure 10

[0018]

Figure 11

[0019]

Figure 12

[0020]

Figure 13

[0021]

Figure 14

Mode for Carrying Out the Invention

[0022] The present object discloses a parking brake function that can be realized using one or more multi-stage transmissions. The present object is applicable to any vehicle equipped with any type of drive system employing one or more multi-stage transmissions, but is particularly suitable for commercial trucks having an electric or hybrid drive system. In some embodiments, the present object can reduce the size and complexity of the vehicle braking system, particularly proximal to the wheels and / or the accelerator. This reduces the overall vehicle weight and enables the vehicle to be equipped with additional and / or alternative vehicle components such as batteries, electric motors, and the like.

[0023] FIG. 1 is a schematic view of a drive system 100 according to an embodiment of a disclosed object having an exemplary differential 5. The drive system 100 / 150 may include a shiftable multi-speed transmission 8 including at least a first drive stage i(1) and a second drive stage i(2). The drive stages i(1) / i(2) may utilize different ratios to operate the electric motor 1 in an optimal performance region during various operating conditions. Rotation from the electric motor 1 or other propulsion source may be input to the multi-speed transmission 8 via an input shaft, chain, belt, gear, or the like of the multi-speed transmission 8. The ratios may be selected, for example, to meet the vehicle's uphill ability requirements from a stationary state such that the vehicle can start on a specific gradient and maintain forward motion on the same gradient. Although referred to as a "transmission", the drive stages i(1) / i(2) disposed within the multi-speed transmission 8 may be realized by gears, pulleys, or sprockets connected by belts and / or chains or the like. The differential 5 may distribute the torque generated by the electric motor 1 to the wheel pair 7. Each wheel of the wheel pair 7 may include an external planetary gear disposed at the outer edge of each wheel, and the ratio between the final stage shaft of the differential 5 driving the wheel pair 7 and the driven wheel is greater than 1. The electric motor 1 is illustrated in FIG. 1 for discussion purposes, but any type of engine, motor, or other propulsion source may be used without departing from the scope of the disclosed object. If one or more electric motors are utilized, the vehicle may include a suitable charging device such as a battery pack, capacitor, or the like, from which current is mainly drawn and power is supplied. The gear actuator 3 may be operated electrically, hydraulically, or pneumatically and may select the drive stages i(1) / i(2) of the multi-speed transmission 8 using the sliding clutch 4. Also, the gear actuator 3 may select the neutral mode (N) of the sliding clutch 4 and disconnect the output shaft of the electric motor 1 from the differential 5 and the wheels 7. Here, the output shaft of the electric motor 1 may be mechanically connected to the input of the multi-speed transmission 8, and their conventions may be used interchangeably with each other. For example, it can be said that the sliding clutch 4 connects the output of the electric motor 1 or equivalently the input of the multi-speed transmission 8 to the drive stages i(1) / i(2), the differential 5, and the wheels 7.As shown in the figure, when the gear actuator 3 is moved to the first mode (1), the sliding clutch 4 can mechanically connect the output shaft of the electric motor 1 to the differential device 5 and the wheels 7 via the first drive stage i(1). When the gear actuator 3 is moved to the second mode (2), the sliding clutch 4 can mechanically connect the output shaft of the electric motor 1 to the differential device 5 and the wheels 7 via the second drive stage i(2). The fourth lock mode (L) can mechanically connect the electric motor 1 to the differential device 5 and the wheels 7 via both the first drive stage i(1) and the second drive stage i(2). As described above, at least the first and second drive stages i(1) / i(2) can utilize different ratios that cannot be simultaneously operated without allowing slip of at least one drive stage i(1) / i(2). Therefore, the fourth lock mode (L) can lock the multi-stage transmission 8 so that both the output shaft and the output shaft mechanically connected to the electric motor 1 do not rotate.

[0024] By being in the fourth lock mode (L), the input gear wheel of the differential device 5, also known as the pinion gear, can be locked in the same way as the ring gear. Each wheel of the wheel pair 7 can be made to be independently rotatable freely in the opposite direction, while being made not to be rotatable simultaneously in the same direction. To prevent the vehicle from rolling, the differential lock 6 can be utilized. The differential lock 6 can be operated to prevent independent rotation in the opposite direction by mechanically connecting the first wheel and the second wheel. The differential lock 6 can be realized by connecting each output shaft of the differential device 5. When the wheel pair 7 is locked, a parking brake mode can be achieved that prevents the vehicle from rolling forward and / or backward. The differential lock 6 can be operated to mechanically connect the wheels 7 after or simultaneously in response to the selection of the fourth lock mode (L) via the gear actuator 3. Alternatively or furthermore, the differential lock 6 may be operated regardless of whether the fourth lock mode (L) is activated, for example, to facilitate wheel towing. The activation of the fourth lock mode (L) by the gear actuator 3 may be inhibited while the vehicle is moving by mechanical and / or electrical means to avoid damage to the first and second drive stages i(1) / i(2).

[0025] The multi-speed transmission 8 may be asynchronous. For the transition between the drive stages i(1) / i(2), various techniques can be utilized. For example, while the vehicle is moving, the transition from the first drive stage i(1) to the second drive stage i(2) can occur by disengaging the first drive stage i(1) so that the electric motor 1 is in the neutral mode. Then, the speed of the output shaft of the electric motor 1 and the connection input of the multi-speed transmission 8 can be adjusted so that the sliding clutch 4 can smoothly engage with the second drive stage i(2) without causing excessive wear or damage. On the other hand, when the vehicle is stopped, the electric motor 1 rotates the input of the multi-speed transmission 8 until the sliding clutch 4 can engage with the second drive stage i(2). If the input of the multi-speed transmission 8 is not aligned so that the sliding clutch 4 can engage with the second drive stage i(2), the input of the multi-speed transmission 8 is further rotated via the electric motor 1 until it reaches the correct engagement position with the second drive stage i(2), and correspondingly, the vehicle wheels 7 can also be rotated. The rotation of the vehicle wheels 7 moves the vehicle by a short distance, such as 5 to 25 mm, preferably 14 mm or less. The gear actuator 3, which can also be used to operate the sliding clutch 4 to engage with the first or second drive stage i(1) / i(2), can also be used to disengage the sliding clutch 4 from the first or second drive stage i(1) / i(2).

[0026] To enable a smooth transition of the sliding clutch 4 based on the selected drive stage i(1) / i(2) and the current vehicle speed, the multi-speed transmission 8 may be asynchronous so that the connected electric motor 1 can appropriately adjust its speed. A smooth transition from one drive stage to another is one of the things designed to give a good ride to the vehicle passengers by relatively reducing sudden acceleration and deceleration and to minimize the wear of the internal components of the multi-speed transmission 8.

[0027] FIG. 2A is a schematic diagram of a drive system 200 according to an embodiment of the disclosure object provided with an exemplary differential device 5. The drive system 200 / 250 is similar to the drive system 100 / 150, but may include two gear actuators 3A / 3B that can be individually operated via individual sliding clutches 4A / 4B. As shown in FIG. 2, when the neutral mode (N) is selected, both the gear actuator 3A and the gear actuator 3B can be operated so as not to engage with their respective sliding clutches 4A / 4B. When the gear actuator 3A operates in the first mode (1), the corresponding sliding clutch 4A can connect the output shaft of the electric motor 1 to the differential device 5 and the wheel 7 via the first drive stage i(1). In the second mode (2) where the gear actuator 3B operates and the gear actuator 3A does not operate, the corresponding sliding clutch 4B can be engaged to connect the output shaft of the electric motor 1 to the differential device 5 and the wheel 7 via the second drive stage i(2). The fourth lock mode (L) can occur when both the gear actuator 3A and the gear actuator 3B are operated to engage with the sliding clutches 4A, 4B, mechanically connecting the output shaft of the electric motor 1 to both drive stages i(1) / i(2). Since the first and second drive stages i(1) / i(2) can utilize different ratios that cannot be operated simultaneously, the fourth lock mode (L) can achieve the parking brake function when the differential lock 6 is activated by locking the drive system 200 / 250 to prevent the wheels 7 of the vehicle from rolling.

[0028] As already explained with reference to FIG. 1, when the lock mode (L) is activated, the input gear-wheel of the differential 5 can be locked. Each wheel of the wheel pair 7 can rotate freely independently in opposite directions, while rotation in the same direction simultaneously can be inhibited. To prevent the vehicle from rolling, the differential lock 6 can be utilized. The differential lock 6 can be operated to prevent independent rotation in opposite directions by mechanically connecting the first wheel and the second wheel. The differential lock 6 can be realized by connecting each output shaft of the differential 5. When the wheel pair 7 is locked, the parking brake function can be achieved. The differential lock 6 can be operated to mechanically connect the wheels 7 after or simultaneously in response to the selection of the fourth lock mode (L) via the gear actuator 3. Alternatively or furthermore, the differential lock 6 may be operated regardless of whether the fourth lock mode (L) is activated. This can be carried out, for example, to facilitate wheel traction. The activation of the fourth lock mode (L) by the gear actuator 3 may be inhibited while the vehicle is moving by mechanical and / or electrical means to avoid damage to the first and second drive stages i(1) / i(2).

[0029] FIG. 2B is a schematic view of a drive system 275 according to an embodiment of a disclosure object similar to the drive system 200 shown in FIG. 2A. In the drive system 275, the sliding clutch 4B is mechanically connected to an elastic coupling and can be actuated only via the gear actuator 3B during the parking brake mode (L). Similar to the drive system 200, the gear actuators 3A / 3B can be individually operable via their respective sliding clutches 4A / 4B. In contrast to the drive system 200, the sliding clutch 4A can be used to engage both the first drive stage i(1) and the second drive stage i(2) during the driving mode, i.e., the first (1) and second (2) modes. The sliding clutch 4B is used only during the parking brake mode (L) and can otherwise be in the neutral mode (N). Therefore, the elastic coupling of the sliding clutch 4B is not used while the vehicle is in motion. Similar to the drive system 200, the first and second drive stages i(1) / i(2) can utilize different ratios that cannot be operated simultaneously. Thereby, the fourth lock mode (L) can lock the drive system 275 to prevent the vehicle wheels 7 from rotating and achieve the parking brake function.

[0030] As already explained with reference to FIG. 1, when the lock mode (L) is activated, the input gear - wheels of the differential 5 can be locked. Each wheel of the wheel pair 7 can rotate freely independently in opposite directions, while rotation in the same direction simultaneously can be inhibited. To prevent the rolling of the vehicle, the differential lock 6 can be utilized. The differential lock 6 can be operated to prevent independent rotation in opposite directions by mechanically connecting the first wheel and the second wheel. The differential lock 6 can be realized by connecting each output shaft of the differential 5. The differential lock 6 can be operated to mechanically connect the wheels 7 after or simultaneously in response to the selection of the fourth lock mode (L) via the gear actuator 3. Alternatively or furthermore, the differential lock 6 may be operated regardless of whether the fourth lock mode (L) is activated. This can be carried out, for example, to facilitate wheel traction. The activation of the fourth lock mode (L) by the gear actuator 3 may be inhibited while the vehicle is in motion by mechanical and / or electrical means to avoid damage to the first and second drive stages i(1) / i(2).

[0031] The elastic coupling mechanically connected to the sliding clutch 4B can improve the parking process and facilitate the parking brake function. When attempting to park the vehicle, the vehicle can be guided to the desired parking position. At this point, the driver may wish to activate the parking brake function. For guidance, the first drive stage i(1) is activated and remains activated. The parking mode is started by activating the second drive stage i(2) with the sliding clutch 4B. Chamfering or tooth - to - tooth engagement of the elastic coupling of the sliding clutch 4B and the second drive stage i(2) is used so that the electric motor 1 does not drive when the sliding clutch 4B and the gear - wheel of the second drive stage i(2) are not aligned. The elastic coupler rotates under the same force as the actuator force when the sliding clutch 4B is engaged.

[0032] In another example, the sliding clutch 4B can be engaged via the gear actuator 3B to operate the second drive stage i(2). When stopped, the engagement of the sliding clutch 4B with the second drive stage i(2) can occur only when the hub of the second drive stage i(2) is correctly aligned with the sliding clutch 4B. For example, the sliding clutch 4B can include dog teeth, toothed selectors or the like that can be aligned with the corresponding toothed portion of the second drive stage i(2). The drive stages i(1) / i(2) can include conjugate teeth formed to mesh with the teeth of the toothed selectors of the sliding clutches 4A / 4B when in tooth-to-tooth position. The electric motor 1 can rotate the input of the multi-stage transmission 8 to align the teeth of the sliding clutch 4B with the second drive stage i(2). To achieve the parking brake function, the drive stage i(1) may be simultaneously engaged via the sliding clutch 4A. Also, the sliding clutch 4A requires alignment with the hub of the first drive stage i(1), which can be accomplished by rotating the input of the multi-stage transmission 8 using the electric motor 1 as described above. Usually, the rotation of the electric motor 1 to align the sliding clutch 4A with the first drive stage i(1) at this point moves the vehicle since the second drive stage i(2) is already engaged. However, since the sliding clutch 4B is mechanically connected to an elastic coupling, a limited rotation of the input can be tolerated without moving the vehicle. In other words, the elastic coupling of the sliding clutch 4B allows the input of the multi-stage transmission 8 to twist in place without conversion to rotation of the wheel pair 7 via the second drive stage i(2), which could occur if no elastic coupling were used. In this way, it is possible to achieve alignment between the first drive stage i(1) hub and the sliding clutch 4A with the second drive stage i(2) engaged without moving the vehicle.

[0033] FIG. 3 is a schematic diagram of a drive system 300 that may include a pair of electric motors 1 / 2 and corresponding pairs of multi-stage transmissions 8A / 8B according to an embodiment of the disclosure object. Each of the first electric motor 1 and the second electric motor 2 can separately drive individual wheels of the wheel pair 7 via the first and second multi-stage transmissions 8A / 8B, respectively. In this way, as applied to FIGS. 4-7, the vehicle can achieve improvements related to efficiency due to no differential loss, safety by the second motor available during loss of the first motor, and dynamics by torque vectoring. Further, each wheel of the wheel pair 7 can implement an individual brake and individual recovery for recharging a charging device attached to the vehicle. Rotation from the electric motor 1 or other propulsion source can be input to the multi-stage transmissions 8A / 8B via input shafts, chains, belts, gears, and the like of the multi-stage transmissions 8A / 8B. Each multi-stage transmission 8A / 8B may have two or more drive stages i(1) / i(2) that can be individually engaged via corresponding sliding clutches 4A-4D by operating corresponding gear actuators 3A-3D. In this way, each multi-stage transmission 8A / 8B can provide at least neutral, first, and second operating modes as described above. In an embodiment, the gear actuators 3A / 3C and 3B / 3D can be simultaneously actuated and deactuated in pairs to maintain the same drive stage i(1) / i(2) for each of the wheels 7. For example, the actuation of the first drive stage i(1) can occur simultaneously for the gear actuators 3A / 3C and the sliding clutches 4A / 4C, and the actuation of the second drive stage i(2) can occur simultaneously for the gear actuators 3B / 3D and the sliding clutches 4B / 4D. Actuating the gear actuators 3A-3D together can form each input of the multi-stage transmissions 8A / 8B corresponding to the wheels of the wheel pair 7. When the wheel pair 7 is locked, a parking brake mode can be achieved. Each wheel of the wheel pair 7 can be independently driven, and no differential is required to distribute torque to the wheels 7. Similarly, in contrast to the drive system layouts 100 and 200, no differential lock is required to lock the wheels 7 in the drive system layout 300.

[0034] FIG. 4 is a schematic view of a drive system 400 according to an embodiment of the disclosed subject matter, further including a shaft lock 12 and being similar to the drive system 300. The shaft lock 12 can be actuated to mechanically connect each wheel of the wheel pair 7. Unlike the drive system 300, when the shaft lock 12 is actuated, either of the operating gear actuators 3A and 3B or gear actuators 3C and 3D can lock both wheels of the wheel pair 7. In other words, the shaft lock 12 can lock both wheels of the wheel pair 7 by locking only a single one of the multi-speed transmissions 8A / 8B. When the wheel pair 7 is locked via the shaft lock 12, a parking brake mode can be realized. As described above, one or more of the multi-speed transmissions 8A / 8B can be locked in a fourth lock mode (L) in which at least two drive stages i(1) / i(2) are simultaneously engaged.

[0035] FIG. 5 is a schematic view of a drive system 500 according to an embodiment of the disclosed subject matter, in which a common gear actuator 3A and 3B are shared between the sliding clutches 4A-4D. More specifically, the gear actuator 3A can be used to engage the sliding clutches 4A and 4D that can be mechanically connected to the first drive stage i(1). The gear actuator 3B can be correspondingly used to engage the sliding clutches 4B and 4C that can be mechanically connected to the second drive stage i(2). When both the gear actuators 3A and 3B are actuated to engage all four sliding clutches 4A-4D, the wheel pair 7 is locked to achieve a parking brake mode. Compared with the drive system 400, cost reduction can be realized by reducing the number of gear actuators 3 used to implement the drive system 500. Further, since the drive system 500 can operate the sliding clutches 4A / 4D and the sliding clutches 4B / 4C in a coordinated manner, the first multi-speed transmission 8A can be locked simultaneously with the second multi-speed transmission 8B, and the differential lock 6 can be made unnecessary to lock both wheels of the wheel pair 7.

[0036] FIG. 6 is a schematic diagram of a drive system 600 according to an embodiment of the disclosed object. As shown in FIG. 6, gear actuators 3A and 3B may be provided to mechanically couple the output shaft of electric motor 1 to multi-speed transmission 8A via first and second sliding clutches 4A and 4B. Gear actuator 3A is deactivated in neutral mode or activated to engage sliding clutch 4A at least to first drive stage i(1), and gear actuator 3B may be deactivated in neutral mode or activated to engage sliding clutch 4B at second drive stage i(2). Engaging clutch 4A at first drive stage i(1) using gear actuator 3A and simultaneously engaging clutch 4B at second drive stage i(2) using gear actuator 3B can achieve a parking brake mode for the first wheel of wheel pair 7. On the other hand, gear actuator 3C may be deactivated in neutral mode or activated to engage via sliding clutch 4C to either at least first drive stage i(1) or second drive stage i(2) of multi-speed transmission 8B. Since sliding clutch 4C cannot simultaneously engage both drive stages i(1) / i(2) to establish a fourth lock mode, shaft lock 12 may be utilized to lock the second wheel when the first wheel is locked via the engagement of sliding clutches 4A and 4B. In other words, shaft lock 12 can lock the second wheel (corresponding to electric motor 2) to the locked first wheel (corresponding to electric motor 1) when activated.

[0037] If there is a defect in one of the associated electronic devices such as the electric motor 1 / 2 or the inverter, the power supply line, or something of the same kind, the remaining electric motor 1 / 2 and the corresponding multi-stage transmission 8A / 8B can be used to transmit power to both wheels of the wheel pair 7 by operating the shaft lock 12. For example, if there is a defect in the electric motor 1, the electric motor 2 can supply power to both wheels of the wheel pair 7 by engaging the shaft lock 12. According to the same example, even if there is a defect in the electric motor 1, the vehicle can still achieve the parking brake mode by operating the shaft lock 12 in conjunction with the engagement of both clutches 4A and 4B or by engaging the clutch 4C with one of the drive stages i(1) / i(2) while simultaneously engaging either the clutch 4A or 4B with the other of the drive stages i(1) / i(2).

[0038] Figure 7 is a schematic diagram of a drive system 700 according to an embodiment of the disclosed subject matter and includes first and second shaft locks 12A / 12B. The shaft locks 12A / 12B can each be operated by one or more gear actuators or the same gear actuator. The drive system 700 includes a first gear actuator 3A and a second gear actuator 3B that can function in a manner similar to the gear actuator 3C of the drive system 600 having at least three drive modes. Specifically, each of the gear actuators 3A and 3B is deactivated in neutral mode and may be activated to engage the sliding clutches 4A / 4B in either the first drive stage i(1) or the second drive stage i(2) of the respective multi-speed transmissions 8A / 8B. Generally, the gear actuators 3A and 3B can be synchronized to engage in the first drive stage i(1) or the second drive stage i(2) simultaneously or in the same time period as described above with reference to the drive system 400. When the operating conditions are different for each wheel of the wheel pair 7, for example, on ice, snow, or during off-road driving, it may be possible to drive the first wheel by the electric motor 1 at a first speed using the first drive stage i(1) while simultaneously driving the second wheel by the electric motor 2 at a second speed using the second drive stage i(2). Similar to the gear actuator 3C of the drive system 600, neither of the gear actuators 3A / 3B can engage both the first and second drive stages i(1) / i(2) individually at the same time, thereby preventing either of the gear actuators 3A / 3B from establishing the fourth lock mode individually. To achieve the parking brake mode in the drive system 700, the gear actuators 3A and 3B can each select different drive stages i(1) / i(2) via the sliding clutches 4A and 4B. For example, the gear actuator 3A can select the second drive stage i(2), and the gear actuator 3B can select the first drive stage i(1). The shaft lock 12B can be disposed between the first and second wheels of the wheel pair 7 to mechanically connect them. However, for example, as a result of engagement in different drive stages, the corresponding electric motors can rotate independently at different speeds and the vehicle wheels 7 can roll, so the shaft lock 12B alone may be insufficient to achieve the parking brake.Therefore, the shaft lock 12A can be provided to inhibit individual rotations by connecting to the output shaft of the electric motor or equivalently to the input of the multi-speed transmission 8A / 8B. When operating simultaneously, the shaft locks 12A and 12B can realize a parking brake function that locks the drive system 700.

[0039] If there is a problem with one of the electric motors 1 / 2 or one of the multi-speed transmissions 8A / 8B, the remaining electric motor 1 / 2 and the corresponding multi-speed transmission 8A / 8B can be used to transmit power to both wheels of the wheel pair 7 by actuating the shaft lock 12B. For example, if there is a problem with the electric motor 1, the shaft lock 12A and the sliding clutch 4A remain disengaged to eliminate and / or reduce possible resistance from the faulty electric motor 1, while the electric motor 2 can supply power to both wheels of the wheel pair 7 through the engagement of the shaft lock 12B. Alternatively or further, if a problem occurs within the multi-speed transmission 8A, for example, the shaft lock 12B can be used in combination with the shaft lock 12A to transmit the cumulative power from both electric motors 1 / 2 to the wheel pair 7 through the sliding clutch 4B and the multi-speed transmission 8B. In this case, the sliding clutch 4A may remain disengaged in neutral mode to separate the faulty multi-speed transmission 8A from the rest of the drive system.

[0040] For each of the drive systems shown in FIGS. 1-8, the engagement of at least two drive stages i(1) / i(2) to achieve the parking brake mode can be designed such that the parking brake function remains even when power is removed from the vehicle. This can be implemented using a self-locking or other latch-type actuator 3, a gear actuator 3, or a spring or similar in the sliding clutch 4. Since the (one or more) gear actuators 3 can be actuated and released by electrical or electronic technology, a release mechanism can be provided to manually release the parking brake mode when the vehicle's power is inaccessible and / or available. The release mechanism may be an auxiliary device 9 implemented in the form of a spindle-shaped screw device, which may be partially electrical or electronic for use when the vehicle power is available. Alternatively or additionally, the auxiliary device 9 may be an electrical or electronic release device that operates via power supplied from an external source not derived from the vehicle, such as a battery of the auxiliary device 9, a household main power supply, another vehicle, or another power source. Alternatively or additionally, the auxiliary device 9 may be mounted in the passenger compartment of the vehicle and electrically connected to the multi-stage transmission 8.

[0041] FIG. 8A is a schematic view of a drive system 800 employing a first embodiment of the auxiliary device 9 and having an exemplary differential device 5. The auxiliary device 9 may employ a release mechanism that enables manual release of the parking brake. The release mechanism may be implemented using, for example, a spindle, a screw device, an electrical device, or the like to enable release of the parking brake mode. As shown in FIG. 8A, the auxiliary device 9 may be implemented by enabling manual disengagement of the sliding clutches 4A and 4B.

[0042] FIG. 8B is a schematic view of a drive system 825 employing a second embodiment of the auxiliary device 9 and including an exemplary differential device 5. The embodiment shown in FIG. 8B may be integrated or combined with the embodiment shown in FIG. 8A, but is shown separately for purposes of simplifying the discussion and illustration. As shown in FIG. 8B, the auxiliary device 9 may employ a manual unlocking mechanism that enables release of the parking brake by disengaging the sliding clutches 4A and 4B. Further, if the gear actuator 3 also actuates and releases the differential lock 6 of the differential device 5, the auxiliary device 9 may also manually release the differential lock 6.

[0043] Figure 9 shows an exemplary flow 900 for parking a vehicle according to an embodiment of the disclosed subject matter. In S901, a request to park a vehicle equipped with at least one multi-speed transmission may be received from a user. The parking request may be received via an input disposed within the vehicle itself, remotely via an electronic device such as a key fob or a mobile phone, or via the Internet, Wi-Fi®, Bluetooth®, RFID, or other transmission medium. The vehicle may employ any of the exemplary drive system layouts shown in FIGS. 1-8, or an alternative drive system layout. In S902, it may be determined whether the vehicle is currently in motion. If the vehicle is in motion, the service brake may be applied to bring the vehicle to a stop (S903). The force applied to apply the service brake may be configurable and / or variable based on the current speed of the vehicle. The service brake may be imposed by the vehicle's processor, the user, or both. Once the vehicle is stationary, the service brake may be held in S904 by the vehicle's processor, the user, or both. To implement the parking brake function, at least two drive stages may be engaged simultaneously in S905. The drive stages may be, for example, a first drive stage and a second drive stage implemented using gears or the like as described above. The first and second drive stages may be engaged within a single or multiple multi-speed transmissions. For example, the first drive stage may be engaged within a first multi-speed transmission while the second drive stage may be engaged within a second multi-speed transmission. The engagement of the first and second drive stages in S905 may occur simultaneously or not. For example, the second drive stage may be engaged first, then the first drive stage may be engaged, and the first and second drive stages may be engaged together.

[0044] The engagement of the first and / or second drive stages may occur after rotation of the input shaft of the first and / or second multi-speed transmission to properly align the hubs of the drive stages (e.g., the first / second drive stage i(1) / i(2)) with the sliding clutch 4. Rotation of the input shaft of the multi-speed transmission may move the vehicle forward and / or backward by a relatively small distance between 5-25 mm, preferably 14 mm or less.

[0045] Other modifications of the drive system include a single-speed transmission disposed between one or more electric motors 1 / 2 and the multi-speed transmission 8.

[0046] FIG. 10 shows an exemplary flow 1000 for releasing the parking brake function. In S1001, a request to release the parking of a vehicle equipped with a multi-speed transmission 8 may be received from the user. The request may be received via an input disposed within the vehicle itself, remotely via a secure electronic device such as a key fob or a mobile phone, or via the Internet, Wi-Fi®, Bluetooth®, RFID, or other transmission media. The vehicle may employ any of the exemplary drive system layouts shown in FIGS. 1-8 or an alternative drive system layout. In S1002, the service brake may be applied by the vehicle's processor, the user, or both. Alternatively or additionally, the hill start assist may be activated. The hill start assist may automatically activate the service brake so that the vehicle does not roll when starting from a stationary state on an incline. In S1003, the vehicle may wait for a selection of a driving gear. The selected gear may be, for example, the "drive" gear and may be selected by the user or automatically by the vehicle's processor. In response to the gear selection, the vehicle's processor may disengage the engagement of at least two simultaneous drive stages and engage a single drive stage of the multi-speed transmission 8 in S1004. The disengagement of the engagement of at least two drive stages may occur after the rotation of the input shaft of at least the first and / or second multi-speed transmission 8 to properly align the hubs of the drive stages (e.g., the first / second drive stages i(1) / i(2)) with the sliding clutch 4. The rotation of the input shaft of the multi-speed transmission 8 may move the vehicle forward and / or backward by a relatively small distance such as 5-25 mm, preferably 14 mm or less. In S1005, the vehicle service brake may be released in response to the reception of an accelerator request. The accelerator request may be transmitted by the vehicle's processor, for example, in response to the user depressing the accelerator pedal.

[0047] The processor-based characteristic embodiments of the objects disclosed herein can be implemented and used in various components and network architectures. FIG. 11 is an exemplary computing device 20 suitable for implementing an embodiment of the object disclosed herein. The computing device 20 may be, for example, a desktop or laptop computer, a gaming console, a game server, a set-top box, or a mobile computing device such as a smartphone, a tablet, or the like. The computing device 20 includes a central processor 24, a random access memory (RAM), a read-only memory (ROM), a memory 27 such as flash RAM or the like, a user display 22 such as a display screen, a user input interface 26 including one or more controllers and related user input devices such as a keyboard, a mouse, a touch screen, and the like, a fixed storage 23 such as a hard drive, a flash drive, and the like, a removable media component 25 operable to control and receive optical discs, flash drives, and the like, and a network interface 29 operable to communicate with one or more remote devices via a suitable network connection. The computing device 20 may include a bus 21 interconnecting the main components of the computing device 20.

[0048] The bus 21 enables data communication between the central processor 24 and one or more memory components that may include RAM, ROM, and other memory as described above. Typically, the RAM is the main memory in which the operating system and application programs are loaded. The ROM or flash memory component may include a basic input / output system (BIOS) that controls basic hardware operations such as the interaction with peripheral components, among other codes. Applications resident on the computer 20 are generally stored and accessed via a computer-readable medium such as a hard disk drive (e.g., fixed storage 23), an optical drive, a floppy disk, or other storage media.

[0049] The fixed storage 23 may be integrated with the computer 20 or may be separate and accessed via other interfaces. The network interface 29 may provide a direct connection to a remote server via a wired or wireless connection. The network interface 29 may use any suitable technology and protocol readily understandable by those skilled in the art, including digital cellular telephones, Wi-Fi (registered trademark), Bluetooth (registered trademark), near-field communication, and the like, to provide such a connection. For example, the network interface 29 may enable the computer to communicate with other computers via one or more local, wide-area, or other communication networks, as described in more detail below.

[0050] Many other devices or components (e.g., a document scanner, a digital camera, etc., not shown) may be connected in a similar manner. Conversely, not all of the components shown in FIG. 11 need to be present to practice the present disclosure. The components may be interconnected in a manner different from that shown. The operation of a computer such as that shown in FIG. 11 is readily known to those skilled in the art and will not be discussed in detail herein. The code for practicing the present disclosure may be stored on a computer-readable storage medium such as one or more memories 27, the fixed storage 23, the removable media 25, or a remote storage location.

[0051] FIG. 12 shows an exemplary network configuration according to an embodiment of the disclosed subject matter. One or more devices 10, 11, such as local computers, smartphones, tablet computing devices, and the like, may be connected to other devices via one or more networks 30. Each device may be a computing device as described above. The network may be a local network, a wide area network, the Internet, or any other suitable communication network, and may be implemented on any suitable platform including wired and / or wireless networks. The devices may communicate with one or more remote devices such as server 13 and / or database 15. The remote devices may be accessed directly by devices 10, 11, or one or more other devices may provide intermediary access such that server 13 provides access to resources stored in database 15. Also, devices 10, 11 may access services provided by remote platform 17 or a remote platform 17 such as a cloud computing arrangement and services. Remote platform 17 may include one or more servers 13 and / or database 15.

[0052] User interface 13, database 15, and / or the processing unit may be part of an integrated system or may include multiple computer systems that communicate via a private network, the Internet, or any other suitable network. One or more processing units may be part of a distributed system, such as, for example, a cloud-based computing system, a search engine, a content delivery system, or the like, that includes or may communicate with database 15 and / or user interface 13.

[0053] Figure 13 shows an exemplary partial system configuration 1300 for enabling a secondary braking function when there is a problem with the normal braking control when the dynamic parking brake function is not available. This parking lock, unlike the current spring brake type parking brake, cannot apply the brake while the vehicle is in motion. Alternatively, a secondary brake can also be realized via a manual control unit. The manual control unit 1310 can be electrically coupled to an electronic brake modulator (EBM) 1330 and an electronic brake system (EBS) control unit 1320. Alternatively or further, the features of the EBS control unit 1320 may be implemented using other types of computing devices configured to apply the vehicle normal brake. For example, the features of the EBS control unit 1320 may be executed by a general-purpose processor or a controller configured to execute instructions stored on a computer-readable storage medium in order to convert the general-purpose processor into a special-purpose processing device. The EBS control unit 1320 may be implemented, for example, using a microprocessor, a microcontroller, a field programmable gate array (FPGA), an application specific integrated circuit (ASIC), and / or software modules executed on a centralized controller that performs other functions and / or cooperates with other vehicle systems. If there is a problem with the foot brake module, the driver can activate the normal brake via the manual control unit 1310. The manual control unit 1310 transmits a brake request 1380 to the EBS control unit 1320 via an electrical signal. If there is a problem with the EBS, the manual control unit 1310 transmits a brake request 1380 to the EBM 1330. The EBM 1330 is a pneumatic backup that supplies an EBS1 channel module 1340 and an EBS2 channel module 1350 when there is a problem with the EBS. A problem with the foot brake module can occur, for example, when a bottle is under the pedal and the driver cannot execute a brake request with their foot. In an embodiment, the electrical connection may be made via a communication path 1361 / 1362 such as a controller area network (CAN).The communication paths 1361 / 1362 can be implemented via a common bus configuration that includes two separate individual two-point connections or communication paths 1361 and 1362, as shown in FIG. 13. The electronic brake modulator 1330 can be connected to the compressed air supply 1301 and configured to distribute the air supply 1301 to the EBS1 channel module 1340 and the EBS2 channel module 1350. The manual control unit 1310 can send a brake request 1380 to the electronic brake modulator 1330 via the communication path 1361 and send the brake request 1380 to the EBS control unit 1320 via the communication path 1362. In response to receiving the brake request 1380, the electronic brake modulator 1330 can modulate the air pressure to the EBS1 channel module 1340 and the EBS2 channel module 1350.

[0054] FIG. 14 shows an exemplary partial system configuration 1400 for enabling a secondary brake function when there is a problem with the service brake control when the dynamic parking brake function is unavailable. The manual control unit 1310 can be electrically connected to the booster 1410 and the electronic brake system (EBS) control unit 1320. In an embodiment, the electrical connection can be made via a communication path 1361 / 1362 such as a controller area network (CAN). The communication path 1361 / 1362 can be implemented via a common bus configuration including two separate individual two-point connections or communication paths 1361 and 1362, as shown in FIG. 14. The booster 1410 is connected to the compressed air supply 1301 and can be configured to regulate the air supply 1301 to the redundant foot brake module 1420. The manual control unit 1310 can send a brake request 1380 to the EBS control unit 1320 via the communication path 1362. If the brake request 1380 is not executed, the brake request 1380 is sent to the booster 1410 via the communication path 1361. In response to receiving the brake request 1380, the booster 1410 can adjust the air pressure to the redundant foot brake module 1420. When the EBS control unit 1320 fails to execute the brake request 1380, the service brake can be actuated by the manual control unit 1310 by sending the brake request 1380 to the redundant foot brake module 1420 via the booster 1410.

[0055] More generally, features enabled by various processors of the present disclosure may be embodied in or include forms of computer-implemented processes and apparatus for practicing those processes. Embodiments may also be embodied in the form of a computer program product having computer program code embodied in a non-transitory and / or tangible medium such as a floppy disk, CD-ROM, hard drive, USB (Universal Serial Bus) drive, or any other machine-readable storage medium, where the computer program code, when loaded and executed on a computer, causes the computer to be an apparatus for practicing embodiments of the disclosure. Embodiments may also be embodied in the form of computer program code, whether stored on a storage medium, loaded and / or executed on a computer, or transmitted via any type of transmission medium such as electrical wiring or cable, optical fiber, or electromagnetic radiation, where the computer program code, when loaded and executed on a computer, causes the computer to be an apparatus for practicing embodiments of the disclosure. When implemented on a general-purpose microprocessor, segments of the computer program code configure the microprocessor to create specific logic circuits.

[0056] In some configurations, a set of computer-readable instructions stored on a computer-readable storage medium may be executed by a general-purpose processor, thereby causing the general-purpose processor or an apparatus including the general-purpose processor to be transformed into a special-purpose apparatus configured to execute or perform the instructions. Embodiments may be implemented using hardware including processors such as general-purpose microprocessors and / or application-specific integrated circuits (ASICs) that embody all or part of the techniques according to embodiments of the disclosure in hardware and / or firmware. The processor may be connected to a memory such as RAM, ROM, flash memory, a hard disk, or any other device capable of storing electronic information. The memory may store instructions adapted to be performed by a processor for executing techniques according to embodiments of the disclosure.

[0057] The foregoing description has been presented with reference to specific embodiments for purposes of illustration. However, the above exemplary discussion is not intended to be exhaustive or limiting of the embodiments of the disclosed subject matter to the precise forms disclosed. Many modifications and variations are possible in light of the above teachings. The embodiments were chosen and described in order to explain the principles of the embodiments of the disclosed subject matter and their practical application, thereby enabling one skilled in the art to utilize the embodiments and various modifications thereof suitable for the particular uses contemplated.

Explanation of Reference Numerals

[0058] 1 Electric motor 2 Electric motor 3 / 3A - 3D Gear actuator 4 / 4A / 4B Sliding clutch 5 Differential device 6 Differential lock 7 Wheel 8 / 8A / 8B Multi - speed transmission 9 Auxiliary device 10 Device 11 Device 12 / 12A / 12B Shaft lock 13 Server 15 Database 17 Remote platform 20 Computing device 21 Bus 22 Display 23 Fixed storage 24 Processor 25 Removable media 26 User input 27 Memory 29 Network interface 30 Network 100 Drive system layout 150 Drive system layout 200 Drive system layout 250 Drive system layout 275 Drive system layout 300 Drive System Layout 400 Drive System Layout 500 Drive System Layout 600 Drive System Layout 700 Drive System Layout 800 Drive System Layout 825 Drive System Layout 850 Drive System Layout 875 Drive System Layout 900 Flow 1000 Flow 1300 System Configuration 1301 Air Supply 1310 Manual Control Unit 1320 Electronic Brake System Control Unit 1330 Electronic Brake Modulator 1340 Electronic Brake System 1-Channel Module 1350 Electronic Brake System 2-Channel Module 1361 Communication Path 1362 Communication Path 1380 Brake Requirement 1400 System Configuration 1410 Brake Booster 1420 Redundant Foot Brake Module

Claims

1. 1. A vehicle driveline for achieving a bi-stable locking parking brake function, comprising: a first multi-speed transmission including a plurality of drive stages and at least one actuator for operating a first drive stage among the plurality of drive stages; a first actuator of the at least one actuator may operate the first drive stage simultaneously with a second drive stage; a first clutch of the first multi-stage transmission for engaging the first drive stage via the first actuator; a second clutch of the first multi-stage transmission for engaging the second drive stage via a second actuator; a resilient coupling mechanically connected to the second clutch, the resilient coupling permits rotation of the input of the first multi-speed transmission to align the first clutch with the first drive stage while the second clutch engages the second drive stage.

2. 2. The vehicle driveline of claim 1, further comprising a second actuator in said at least one actuator for actuating said second drive stage simultaneously with said first drive stage actuated by said first actuator.

3. 3. The vehicle drive system according to claim 2, further comprising a second multi-stage transmission including a plurality of drive stages and a third actuator and a fourth actuator for simultaneously operating a first drive stage and a second drive stage among the plurality of drive stages.

4. an output shaft lock for mechanically connecting an output of the first multi-speed transmission with an output of the second multi-speed transmission while the first drive stage and the second drive stage are simultaneously operated; 2. The vehicle driveline of claim 1, wherein the second drive stage that is activated is a plurality of drive stages of the first multi-speed transmission or a plurality of drive stages of the second multi-speed transmission.

5. an input shaft lock that, when actuated, mechanically connects the input of the first multi-speed transmission with the input of the second multi-speed transmission; 3. The vehicle driveline of claim 2, further comprising an output shaft lock for, when actuated, mechanically connecting an output of the first multi-speed transmission with an output of the second multi-speed transmission.

6. the first drive stage having a first ratio; 2. The vehicle driveline of claim 1, wherein said second drive stage has a second ratio different from said first ratio.

7. The vehicle drive system according to claim 1, further comprising an auxiliary device for manually deactivating the first drive stage or the second drive stage.

8. A commercial vehicle comprising at least one driven axle, at least one service brake, at least one propulsion engine and a wheel pair, characterized in that the parking brake function of the vehicle is achieved by the vehicle drive system according to claim 1, which provides bistable locking means acting on both wheels.

9. A first multi-stage transmission having a first drive stage actuated by a first actuator and connected to a first wheel of the wheel pair, A second multi-stage transmission having a second drive stage actuated by a second actuator and connected to a second wheel of the wheel pair, The commercial vehicle according to claim 8, characterized in that the parking brake function is at least partially achieved by simultaneously actuating the first drive stage and the second drive stage.

10. The commercial vehicle according to claim 9, further comprising an output shaft lock for connecting the first wheel of the wheel pair to the second wheel of the wheel pair when actuated.

11. The commercial vehicle according to claim 9, further comprising an input shaft lock for connecting the input of the first multi-stage transmission to the input of the second multi-stage transmission when actuated.

12. The commercial vehicle according to claim 9, characterized in that the first drive stage has a first ratio different from the second ratio of the second drive stage.

13. An elastic coupling, A sliding clutch having a toothed selector connected to the elastic coupling and allowing limited rotational movement of the toothed selector with respect to the sliding shaft of the sliding clutch, The commercial vehicle according to claim 9, characterized in that the sliding clutch is actuated by the second actuator.

14. A multi-stage transmission having a plurality of drive stages, An actuator, The commercial vehicle according to claim 8, further comprising a sliding clutch that simultaneously engages the first drive stage and the second drive stage when actuated by the actuator.

15. The first drive stage or the second drive stage includes conjugate teeth, The commercial vehicle according to claim 13, characterized in that the teeth of the toothed selector are formed to engage the conjugate teeth when in tooth-to-tooth position.

16. The commercial vehicle further comprises an external planetary gear disposed at the outer edge of each wheel of the driven axle. The commercial vehicle according to claim 8, characterized in that the ratio between the final stage shaft of the differential device driving the wheel pair and the wheel is greater than 1.

17. The commercial vehicle according to claim 8, further comprising a manual control unit for actuating the bistable locking means when the commercial vehicle is stationary.

18. Further comprising an electronic brake control unit, The commercial vehicle according to claim 8, characterized in that when the commercial vehicle is moving, the manual control unit is configured to send a brake request to the electronic brake control unit via an electronic signal to actuate at least one service brake.

19. A redundant foot brake module for a redundant brake, and A booster, further comprising, The commercial vehicle according to claim 18, characterized in that the manual control unit is configured to send a brake request to the booster via an electronic signal to actuate the redundant foot brake module when the electronic brake control unit cannot execute the brake request.

Images