Drive unit for a vehicle powered by muscle and / or motor power

Abstract

Drive system for a muscle- and / or motor-powered vehicle, in particular a pedelec, S-pedelec or e-bike, comprising a first drive unit and at least a second drive unit, at least one sensor unit and at least one control unit, wherein the first drive unit is configured to assist a torque at a crankshaft of the vehicle, wherein the second drive unit is configured to generate a torque at a hub of the vehicle, in particular a rear wheel hub, wherein the at least one sensor unit is configured to determine a driving situation and / or operating state of the vehicle, such that the at least one control unit controls the first drive unit and / or the at least second drive system in such a way that a drive combination optimized for the driving situation and / or the operating state is established.

Description

[0001] The present invention relates to a drive system of a vehicle with electric motor drive assistance, in particular a vehicle operated by muscle and / or motor power, for example a pedelec, S-pedelec or e-bike.

[0002] The invention also relates to a vehicle comprising a drive system according to the invention and a method for controlling the drive system. State of the art

[0003] IN 2020 410 450 25 A discloses a drive system that uses artificial intelligence to control a vehicle powered by a mid-engine and a hub motor. Electric bicycles equipped with more than one drive unit are also known, for example, from VanMooF. Furthermore, DE 10 2020 215 222 B4 discloses a method in which a drive unit is controlled depending on a pitch angle. Disclosure of the invention

[0004] The drive system according to the invention for a vehicle operated by muscle and / or motor power with the features of claim 1 has the advantage that the at least one control unit controls a first drive unit and / or the at least second drive system in such a way that a drive combination optimized for a driving situation and / or the operating state is established. For this purpose, the drive system comprises at least one sensor unit and at least one control unit, wherein the first drive unit is configured to assist a torque at a crankshaft of the vehicle, wherein the second drive unit is configured to generate a torque at a hub of the vehicle, in particular a rear wheel hub, and wherein the at least one sensor unit is configured to determine the driving situation and / or the operating state of the vehicle.

[0005] In particular, the drive system according to the invention optimizes a pedelec, S-pedelec, or eBike with more than one drive unit by controlling the drive system depending on the riding situation or operating state. The drive system according to the invention improves riding comfort and the range of a battery module, while simultaneously increasing safety. Especially at an operating point of maximum power and torque values, the drive system according to the invention can optimally support the driver of the vehicle.

[0006] The drive system comprises all components essential for control, in particular a first, a second, and, most particularly, a third drive unit. A drive unit has an electric machine comprising a rotor and a stator. All drive units have in common that they each further comprise a housing, wherein the electric machine is accommodated in the housing. Furthermore, further components of the drive unit, such as a transmission and electronic components, can be accommodated. In the case of the first drive unit, the drive unit is configured to support a torque on a crankshaft of the vehicle.This type of drive unit is characterized by a potentially high torque output, which can lead to a disproportionate load on a drive train at torques > 100Nm and components such as the connecting link, pinion or chainring must be replaced at very short intervals.

[0007] In the case of the second drive unit, the drive unit is configured to generate a torque at a hub of the vehicle, in particular a rear wheel hub. Hub drives are characterized by the fact that an assist torque can be delivered to a front or rear wheel, in particular without a connecting link, such as a chain or belt. In particular, the hub drive is independent of a crank position or a torque applied to the connecting link during a gear shift, which can, for example, increase wear.

[0008] The drive units are also designed for walk assistance. Walk assistance can only be activated when the rider is not pedaling and the vehicle speed is less than or equal to a threshold, for example, less than or equal to six kilometers per hour (km / h). When walk assistance is activated, the drive unit advantageously generates a slowly increasing torque until the vehicle reaches walking speed. Due to its design, the hub drive also has disadvantages. Because the housing is essentially thermally decoupled from hot components inside the housing, the hub drive cannot generate high power sustained, which can lead to a drop in performance, or what is known as "derating."

[0009] The drive system further comprises at least one sensor unit, which is configured to determine a driving situation and / or an operating state of the vehicle. The at least one sensor unit serves to provide a measurement signal to a control unit. This provision also includes, in particular, the generation and processing of the measurement signal. The at least one sensor unit can be a single sensor; alternatively, the at least one sensor unit can also have a plurality of sensors. The at least one sensor unit can, in particular, comprise sensors for determining at least one rotation rate, an acceleration, a magnetic field, sensors for determining position, or the like. Furthermore, the sensor unit can detect signals generated in functional components of the vehicle, for example a gearshift device.In particular, the at least one sensor unit can be arranged both on a frame component of the vehicle and in the housing of a drive unit. For example, the at least one sensor unit is a multi-axis inertial sensor system.

[0010] The driving situation describes, in particular, a state of motion of the vehicle. According to the invention, the driving situation should be a situation detected by the at least one sensor unit and characteristic of the sensor signals, for example, an acceleration of the vehicle, a deceleration, clearly identifiable signals such as those of the gearshift device, or the like.

[0011] The operating state should be understood, in particular, as a state of the drive system. In particular, a state of the components comprising the drive system is considered. For example, the operating state is determined taking into account the temperature of a motor of the drive unit, the temperature of a battery, the degree of load on a drive unit, or the like. Furthermore, the operating state can also be understood as an algorithm that, for example, initiates an optimization process, taking into account the measured values ​​determined by the sensor unit.

[0012] The optimized drive combination is ensured by the control unit. The input variable is the determined driving situation and / or operating mode. The optimized drive combination differs from a standard drive combination in that it is adapted to the driving situation or operating mode. In particular, the optimized drive combination is time-limited. This allows the vehicle to be operated particularly comfortably, efficiently, and reliably. Preferably, the first drive unit, the second drive unit, and especially the third drive unit are controlled in such a way that they deliver an assistance torque adapted to the driving situation or operating mode.

[0013] In one embodiment, the drive system comprises a third drive unit, wherein the third drive unit is configured to generate a torque at a hub, in particular a front-wheel hub. Particularly advantageous drive combinations can be achieved using a third drive unit. In particular, a higher combined power of the drive units can be generated. Shifting an assist torque to the front wheel can be advantageous, for example, in a situation in which the rear wheel is subject to slippage.

[0014] In one embodiment, the at least one sensor unit is arranged in a housing of the first drive unit and is configured to determine an operating state of the first drive unit and / or a driving situation of the vehicle. The use of the sensors assigned to the respective drive unit is particularly advantageous, since the optimal drive combination can be compiled from the local measurement signals of the sensor units. Each drive unit, for example, has a different temperature, which can lead to a premature reduction in power. To avoid this exemplary case, the assist torque is shifted to one drive.

[0015] In particular, the second drive unit comprises a further sensor unit, which is arranged in a housing of the second drive unit and is configured to determine an operating state of the second drive unit and / or a driving situation of the vehicle. In particular, the third drive unit comprises a further sensor unit, which is arranged in a housing of the third drive unit and is configured to determine an operating state of the third drive unit and / or a driving situation of the vehicle.

[0016] In one embodiment, the driving situation relates to a gear shift, and the control unit controls the drive system such that a load on a connecting link is reduced, and the optimized drive combination is adjusted, in particular, such that the first drive unit reduces an assistance torque. A reduction in the load on the drive train is advantageously achieved. In particular, the control unit controls the drive system such that driving occurs without an interruption in tractive force. In particular, the first drive unit reduces or interrupts the assistance in order to reduce chain tension and minimize the load on the drive train during a gear shift, wherein the drive train comprises an output pinion, a connecting link, and the gearshift device. In particular, the second drive unit is activated or briefly increases the assistance in order to avoid the interruption in tractive force.

[0017] In one embodiment, the driving situation relates to starting off, and the control unit controls the drive system such that starting off is possible essentially independently of the selected shift position of a gearshift device, and the optimized drive combination is adjusted in particular such that the second drive unit has a higher level of assistance than the first drive unit. This advantageous embodiment provides particularly reproducible assistance such that starting off is possible even if an incorrectly engaged gear, for example, a gear ratio that is too high. Starting off can be enabled, for example, by the second drive unit, which is independent of the gearshift position.In one embodiment, the optimized drive combination is adjusted in such a way that, when a correctly engaged gear is engaged, a maximum starting torque is generated by the first and second drive units. This advantageously increases safety, for example, by reaching a stable driving state as quickly as possible.

[0018] In one embodiment, the driving situation relates to driving with slippage. The control unit controls the drive system in such a way that the driving with slippage is reduced and the optimized drive combination is adjusted in such a way that the first drive unit and in particular the second drive unit reduce their assistance, and in particular the second drive unit switches to generator mode. Slippage is particularly advantageously reduced when the assistance torque is reduced. Driving with slippage can occur during vehicle acceleration. For example, slippage can occur when starting off on unpaved ground, which can be reduced by reducing the assistance torque.

[0019] In one embodiment, the driving situation relates to driving on an incline and the control unit controls the drive system in such a way that the optimized drive combination is adjusted in particular such that the assistance torque oscillates from the first drive unit to the second drive unit. When driving on an incline, in particular when driving uphill, the optimized drive combination is adjusted in particular by avoiding overheating while simultaneously providing the highest possible assistance. Preferably, there is a change between the first and the second drive unit and between maximum power and significantly reduced power, for example in order to incorporate targeted cooling phases. Preferably, the total power of the first and the second drive unit remains constant. This leads to pleasant and natural driving behavior.In an alternative embodiment, the optimized drive combination is achieved in particular by a highest possible, continuous support torque through a combination of the drive unit and the second drive unit.

[0020] In one embodiment, the driving situation involves driving at a limit speed, and the optimized drive combination is adjusted in particular such that the total power of the drive units is increased. A limit speed can, for example, be a legally prescribed maximum speed. A limit speed can be the maximum speed that can be generated by all drive units.

[0021] In one embodiment, the driving situation relates to walking assistance from the first drive unit and the second drive unit, and the control unit controls the drive system such that the optimized drive combination is adjusted in particular such that the walking assistance is essentially reproducible, wherein the walking assistance is preferably independent of a selected gear position of the gearshift device. Reproducible walking assistance means that an assistance torque develops without the influence of the engaged gear, such that the second drive unit, which is independent of the gearshift position, generates the assistance torque. It is particularly advantageous that the gear ratio of the second drive unit is always constant and known. Thus, with walking assistance, acceleration to the desired walking speed can be achieved reproducibly quickly and strongly.In particular, the assistance torque is generated without turning the crank.

[0022] In one embodiment, the operating state relates to an optimization of the range and the optimized drive combination is set in particular such that the drive unit is operated in a generator mode, all drive units are regulated down in the event of thermal overload or, in the event of poor efficiency of the first drive unit, the support of the first drive unit is reduced.

[0023] In one embodiment, the operating state relates to an optimization of the range and the control unit controls the drive system in such a way that the first drive unit, the second drive unit and in particular the third drive unit are operated in a generator mode, the first drive unit, the second drive unit and in particular the third drive unit are regulated down in the event of thermal overload or in the event of poor efficiency of the first drive unit, the support by the first drive unit is reduced.

[0024] The invention further relates to a vehicle with a drive system as described above.

[0025] The invention further relates to a method for controlling a drive system according to the embodiments described above, the method carrying out the following steps: • Determining a driving situation and / or an operating state. • Determine an optimized drive combination. • Controlling the drive system taking into account the determined driving situation and / or operating status. Short description of the characters Fig. 1 shows a schematic view of a bicycle with an embodiment of the drive system according to the invention and Fig. 2 a method for controlling an inventive Drive system.Embodiments of the invention

[0026] Identical elements or elements with the same function are provided with the same reference numbers in the figures.

[0027] Fig. 1 shows a simplified schematic view of a bicycle 100, in particular a pedelec or S-pedelec, with a first drive unit 2, a second drive unit 3, and a third drive unit 4. The first drive unit 2 is configured to assist a rider torque acting on the crankshaft 10 and to transmit it to an output pinion 107, which is in direct engagement with the connecting element 101 for driving the bicycle 100. The first drive unit 2 is designed as a mid-engine. The bicycle 100 has a front wheel 115 and a rear wheel 116, with the second drive unit 3 being arranged on a rear wheel hub 130 and the third drive unit being arranged on a front wheel hub 131. The rear wheel 116 on the rear wheel hub 130 is driven on the one hand by means of a connecting element 101, in particular a chain, and by means of the first drive unit 2 and by a pedal force of the cyclist on the pedals 108.On the other hand, the second drive unit 3 arranged in the rear wheel hub 130 is configured to drive the rear wheel 116 simultaneously or exclusively. The second drive unit 3 and the third drive unit 4 are designed as hub motors. It is particularly advantageous that the gear ratio of the second drive unit 3 and the third drive unit 3 is always constant and thus known. Thus, for example, with push assistance, a reproducible and slowly increasing torque can be achieved until a walking speed of the vehicle is reached. In particular, an assistance torque is generated without co-rotation of the crank 119.

[0028] The pedals 108 are connected to the cranks 119, which in turn are connected to different ends of the crankshaft 10. The output pinion 107 is rotationally fixedly connected to an output shaft (not shown) of the first drive unit 2, wherein the output shaft is operatively connected to the pedal shaft 10.

[0029] Furthermore, the drive system 1 comprises at least one sensor unit 117, which is configured to determine a driving situation and / or operating state of the vehicle 100. The at least one sensor unit 117 serves to provide a measurement signal to a control unit 118. The provision also includes, in particular, the generation and processing of the measurement signal. The at least one sensor unit 117 is configured in the Fig. 1, the sensor unit 117 is embodied as an inertial sensor system 117, but in another embodiment, it can also comprise a plurality of sensors. For example, the sensor unit 117 can combine several measurement signals to determine a driving situation. For this purpose, sensors for determining acceleration, a magnetic field, sensors for determining position, such as GPS, or the like, are available. Furthermore, the sensor unit 117 can detect signals generated in functional modules of the vehicle 100, for example, a gearshift device 102. The sensor unit 117 is arranged in a housing (not shown) of the first drive unit 2 and is thus protected from the effects of the weather. At the same time, the sensor unit is arranged on a circuit board of the control unit 118, which is also arranged in the housing of the first drive unit 2.

[0030] The frame component 113 of the vehicle 100 comprises, in particular, a seat tube 106, a down tube 111, a top tube 110, a head tube 112, and a chainstay 105, which are permanently connected to one another, for example, welded together. Furthermore, the bicycle 100 has a steering unit 120. Schematically illustrated is an input device 11 of the gearshift device 102, which, like a user display 122 and a braking device 121, is attached to the steering unit 120.

[0031] If a user actuates the input device 11 of the gearshift device 102, a shifting process for moving the connecting link 101 is initiated, such that a control signal is transmitted to the control unit 118. The control unit 118 controls the drive system 1 such that a load on a connecting link 101 is reduced. The optimized drive combination is adjusted such that the first drive unit 2 reduces an assist torque and thus, in particular, only a low torque is applied to the output pinion 107. A reduction in the load on the drive train, in particular the gearshift device 102, the connecting link 101, and the output pinion 107, is advantageously achieved and thus prevents premature wear or a faulty shifting process. In particular, the drive system 1 is controlled such that driving occurs without an interruption in tractive force.In particular, during a gear shift, the second drive unit 3 is activated or briefly increases the assistance to avoid an interruption in the tractive force to the connecting link 101. If the driving situation involves starting off, the drive system is controlled such that starting off is possible essentially independently of a selected shift position of a gearshift device 102. The optimized drive combination is adjusted such that the second drive unit 3 has a higher level of assistance than the first drive unit 2. If, for example, a user drives to a stop and forgets to shift into a shift position optimized for starting off, the second or third drive unit, due to its independence from the gearshift device, can compensate for this error and enable starting off.Activating the first drive unit 2 with an incorrectly engaged gear results in high torques, particularly over 100 Nm, during a starting maneuver. Activating the second and third drive units 3, 4 for starting advantageously increases safety, for example, to achieve a stable riding condition as quickly as possible. This is particularly relevant for a cargo bike, since in addition to the engaged gear, large loads can be moved, making starting off fundamentally more difficult.

[0032] In one embodiment, the driving situation relates to driving with slippage, so the control unit 118 controls the drive system 1 in such a way that the driving with slippage is reduced and the optimized drive combination is adjusted in particular such that the first drive unit and in particular the second drive unit reduce their assistance, and in particular the second drive unit switches to generator operation. At the same time, in the Fig. In the embodiment shown in Figure 1, the third drive unit 4 assumes part of the assist torque. Furthermore, slippage can also occur during braking, which can be reduced, in particular, by the non-locked wheel (115, 116) in generator mode for brake assistance. Particularly advantageously, driving with slippage is reduced by reducing the assist torque. Driving with slippage can occur during vehicle acceleration. For example, slippage can occur when starting off on unpaved ground, which can be reduced by reducing the assist torque.

[0033] The drive unit 2 is connected to a battery module 109 via a cable (indicated) and is powered by it. The second and third drive units 3, 4 are also powered by the battery module 109 (not shown).

[0034] Fig.2 shows a method 140 according to the invention for controlling the drive system 1. The following steps are carried out: • Determining a driving situation and / or an operating state (150) • Determining an optimized drive combination (151) • Controlling (152) the drive system (1) taking into account the determined driving situation and / or operating state. QUOTES CONTAINED IN THE DESCRIPTION

[0000] This list of documents submitted by the applicant was generated automatically and is included solely for the convenience of the reader. This list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions. Cited patent literature

[0000] DE 10 2020 215 222 B4

[0003]

Claims

[1] Drive system (1) for a muscle- and / or motor-powered vehicle (100), in particular a Pedelec, S-Pedelec or Ebike, comprising a first drive unit (2) and at least one second drive unit (3), at least one sensor unit (117) and at least one control unit (118), wherein the first drive unit (2) is arranged to support a torque on a crankshaft (10) of the vehicle (100), wherein the second drive unit (3) is designed to generate a torque at a hub (130, 131) of the vehicle, in particular a rear wheel hub (132), wherein the at least one sensor unit (117) is configured to determine a driving situation and / or operating state of the vehicle (150), characterized bythat the at least one control unit (118) controls (151) the first drive unit (2) and / or the at least second drive system (3) in such a way that a drive combination optimized for the driving situation and / or the operating state is established. [2] Drive system according to claim 1, further comprising a third drive unit (4), wherein the third drive unit (4) is configured to generate a torque at a hub (130, 131), in particular a front wheel hub (131), wherein the at least one control unit (118) controls the first drive unit (2) and the at least second drive system (3) and / or the third drive unit (4) in such a way that a drive combination optimized for the driving situation and / or the operating state is established. [3] Drive system according to one of claims 1 or 2, characterized by that the at least one sensor unit (117) is arranged in a housing of the first drive unit (2). [4] Drive system according to one of the preceding claims, characterized by that the driving situation is a gear shifting operation and the control unit (118) controls the drive system (1) in such a way that a load on a connecting member (101) is reduced, and the optimized drive combination is adjusted in particular in such a way that the first drive unit (2) reduces an assistance torque. [5] Drive system according to one of the preceding claims, characterized by that the driving situation relates to starting off and the control unit controls the drive system (1) in such a way that starting off is possible essentially independently of a selected switching position of a gearshift device (102) and the optimized drive combination is set in particular in such a way that the second drive unit (3) has a higher level of assistance than the first drive unit (2). [6] Drive system according to one of the preceding claims, characterized bythat the driving situation concerns driving with slippage and the control unit (118) controls the drive system (1) in such a way that the driving with slippage is reduced and the optimized drive combination is adjusted in particular in such a way that the drive unit (2, 3) reduces its support and in particular switches the second drive unit (3) to generator operation. [7] Drive system (1) according to one of the preceding claims, characterized by that the driving situation concerns driving on an incline and the control unit (118) controls the drive system (1) in such a way that the optimized drive combination is adjusted in particular in such a way that an assistance torque oscillates between the first drive unit (2) and the second drive unit (3). [8] Drive system (1) according to one of the preceding claims, characterized bythat the driving situation is driving at a limit speed and the optimized drive combination is adjusted in particular in such a way that a total power of the drive units (2, 3, 4) is increased. [9] Drive system (1) according to one of the preceding claims, characterized by that the driving situation relates to a pushing assistance of the drive units (2, 3) and the control unit (118) controls the drive system (1) in such a way that the optimized drive combination is adjusted in particular in such a way that the pushing assistance is substantially reproducible, wherein the pushing assistance is preferably independent of a selected switching position of the gearshift device (102). [10] Drive system according to one of the preceding claims, characterized bythat the operating state relates to an optimization of the range and the control unit (118) controls the drive system (1) in such a way that the drive unit (2, 3, 4) is operated in a generator mode, the drive units (2, 3, 4) are regulated down in the event of thermal overload or in the event of poor efficiency of the first drive unit (2), the support by the first drive unit (2) is reduced. [11] Vehicle (100) with a drive system (1) according to one of claims 1 to 10. [12] Method (140) for controlling a drive system (1) according to one of claims 1 to 10, characterized by the following steps: • Determining a driving situation and / or an operating state (150) • Determining an optimized drive combination (151) • Controlling (152) the drive system (1) taking into account the determined driving situation and / or operating state.

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