Method and drive unit for starting a primary drive machine

Abstract

The invention relates to a method for starting a primary drive machine, in particular an internal combustion engine, in an electric driving mode of a drive unit and to a drive unit for a motor vehicle, in particular a motorcycle (11), comprising a primary drive machine (ICE), a secondary drive machine (EM), and a transmission (13). The drive unit (12) has three shifting elements which are paired with the planetary gear set, the input shaft (14), and the primary drive machine (ICE). Thus, the planetary gear set can be blocked, and the input shaft (14) and the primary drive machine (ICE) are blocked in at least one rotational direction.

Description

[0001] Method and drive unit for starting a primary drive machine

[0002] The invention relates to a method for starting a primary drive machine, in particular an internal combustion engine, during an electric driving mode of a drive unit and a drive unit for a motor vehicle, in particular for a motorcycle, with a primary drive machine, a secondary drive machine and a transmission, which drive unit has the following:

[0003] • a first input shaft;

[0004] • an output shaft;

[0005] • an intermediate shaft arranged parallel to the input shaft and connected to the output shaft;

[0006] • a planetary gear set having a first, second and third member, the first member being connected to the primary drive machine, the second member being connected to the secondary drive machine and the third member being connected to the first input shaft;

[0007] • a first switching element which is designed to connect two members of the planetary gear set to one another in a first switching position in a rotationally fixed manner and to block the planetary gear set in this way;

[0008] • a switching element assigned to the input shaft for blocking the input shaft against rotation in at least one direction of rotation;

[0009] • a switching element assigned to the primary drive machine for blocking the primary drive machine against rotation in at least one direction of rotation;

[0010] • a gear pair arrangement with several gear pairs, each gear pair having a fixed gear and a loose gear, each loose gear being able to be activated or deactivated via a switching element assigned to the loose gear; wherein

[0011] • the idler gears of at least two gear pairs are rotatably mounted on the intermediate shaft, and the fixed gears of these at least two gear pairs are arranged in a rotationally fixed manner on the input shaft.

[0012] The invention further relates to a motor vehicle, in particular a motorcycle, with such a drive unit. The object of the invention is to provide a method and a drive unit for starting a primary drive machine, in particular an internal combustion engine, during an electric driving mode.

[0013] The object is achieved by a method and a drive unit according to the independent claims.

[0014] The drive unit according to the invention has shafts arranged parallel to one another, namely input, intermediate and output shafts.

[0015] A transmission of the drive unit according to the invention is preceded - in the power flow - by a planetary gear set, the first member of which is rotationally connected to a primary drive motor, the second member (P2) to a secondary drive motor, and the third member to the input shaft. The transmission has a gear pair arrangement with several gear pairs, so that at least two, in particular at least four, different gear ratios can be engaged. Each gear pair has a fixed gear and an idler gear, wherein each idler gear can be activated or deactivated, i.e., engaged or disengaged, via a shifting element assigned to the idler gear. The idler gears of at least two gear pairs are rotatably mounted on the intermediate shaft, the fixed gears of these at least two gear pairs being rotationally fixed on the input shaft (14).

[0016] To block the input shaft of the drive unit according to the invention, a switching element is assigned to the input shaft. This can block the input shaft in at least one direction of rotation. This can advantageously be a non-controllable switching element, such as a freewheel, which only allows rotation of the input shaft in the forward direction of travel of the motor vehicle. This has the advantage that, due to its design, one direction of rotation is blocked by the freewheel without the need for control. The terms "control," "controllable," or "control" are used in the sense of the invention to also include regulation. Likewise, it can advantageously be a controllable claw brake, whereby the input shaft can be blocked in both directions of rotation.In an advantageous embodiment, the shifting element assigned to the input shaft is designed as a controllable dog brake and combined with the shifting element assigned to the planetary gear set, which blocks the planetary gear set. Thus, both functions can be implemented by a single actuator. In this advantageous embodiment, the combined shifting element consisting of the shifting element assigned to the input shaft and the shifting element assigned to the planetary gear set has three shift positions: a neutral position, a first shift position in which the planetary gear set is locked, and a second shift position in which the input shaft is locked.

[0017] To block the primary drive shaft of the drive unit according to the invention, a switching element is assigned to the primary drive shaft. This can block the primary drive shaft in at least one direction of rotation. This can advantageously be a non-controllable switching element, such as a freewheel, which only allows rotation of the primary drive shaft in the direction in which the primary drive machine is normally operated. This has the advantage that, due to its design, one direction of rotation is blocked by the freewheel without the need for control. The terms "control," "controllable," or "control" are used in the sense of the invention to also include regulating. Likewise, it can advantageously be a controllable claw brake, whereby the primary drive shaft can be blocked in both directions of rotation.

[0018] In an advantageous embodiment, the shifting element assigned to the primary drive shaft is designed as a controllable dog brake and combined with the shifting element assigned to the planetary gear set, which blocks the planetary gear set. Thus, both functions can be realized by a single actuator. In this advantageous embodiment, the combined shifting element, consisting of the shifting element assigned to the primary drive shaft and the shifting element assigned to the planetary gear set, has three shift positions: a neutral position, a first shift position in which the planetary gear set is locked, and a second shift position in which the primary drive shaft is locked.

[0019] The drive unit according to the invention advantageously enables five gears in ICE or hybrid mode with only four gear meshes. It also has the advantage that only four or five shift elements enable five gears in ICE or hybrid mode, four gears in electric mode (EV mode), battery charging, and starting of the primary drive motor. The full range of functions is advantageously already possible with a secondary drive motor of approximately 15% of the primary drive motor's power, allowing the use of an electric motor with a voltage of 48V, for example.

[0020] The drive unit according to the invention also makes it possible to do without friction clutches and synchronizations.

[0021] The drive unit according to the invention has active torque support by the secondary drive machine during at least one gear change.

[0022] The drive unit according to the invention and the method according to the invention make it possible to start the primary drive machine with high torque at a standstill and during an electric driving mode.

[0023] In an advantageous embodiment of the invention, it is provided that the first member of the planetary gear set is designed as a ring gear, the second member of the planetary gear set is designed as a sun gear and the third member of the planetary gear set is designed as a web.

[0024] The following applies to the standard translation i 0PGS of the planetary gear set PGS (i.e. with the carrier held in place): where zi is the number of teeth on the ring gear and z2 is the number of teeth on the sun gear. The negative sign results from the change in direction of rotation.

[0025] In an extremely compact embodiment of the invention, at least one shifting element is formed by an axially displaceable shifting sleeve, preferably an axially displaceable double shifting sleeve. At least one shifting element advantageously has two shift positions and preferably a neutral position between a first and a second shift position. It is particularly advantageous if a shifting element assigned to a loose gear is formed integrally with a fixed gear of at least one adjacent gear pair. This can save installation space and the number of parts. The fixed gear is displaced axially with the shifting element during the shifting process. This design requires spur gearing of the gears of the affected gear pair.

[0026] The invention is explained in more detail below with reference to the non-limiting embodiments shown in the figures. These schematically show:

[0027] Fig. 1 shows a motor vehicle with a drive unit according to the invention,

[0028] Fig. 2 shows a drive unit according to the invention in a first embodiment,

[0029] Fig. 3 shows a drive unit according to the invention in a second embodiment,

[0030] Fig. 4 shows a drive unit according to the invention in a third embodiment,

[0031] Fig. 5 shows a drive unit according to the invention in a fourth embodiment,

[0032] Fig. 6 shows a drive unit according to the invention in a fifth embodiment,

[0033] Fig. 7 a development of the outer surface of a switching unit designed as a switching drum,

[0034] Fig. 8 shows an upper and lower diagram with the steps of a method according to the invention for starting a primary drive machine, these steps being illustrated in Figs. 9 to 14 using the concrete example of a drive unit according to the third embodiment variant from Fig. 4.

[0035] Fig. 1 shows a motorcycle 11 with a drive unit 12 according to the invention, consisting of a primary drive motor ICE, a secondary drive motor EM, and a transmission 13 with parallel input shafts 14, 16, and 17 arranged transversely to the direction of travel. The output shaft 17 is connected to a rear wheel 19 of the motorcycle 1 via a final drive FD, formed in the illustrated embodiment by a traction transmission, for example via a drive chain 18. The primary drive motor ICE is formed in the exemplary embodiments by an internal combustion engine, and the secondary drive unit EM by an electric machine.

[0036] Fig. 2 shows the drive unit 12 from Fig. 1 in detail. The transmission 13 of the drive unit 12 is designed in each of the embodiment variants to perform at least one gear change with active torque support by the secondary drive machine EM.

[0037] The transmission 13 has an input shaft 14. The output shaft 17 is connected in a rotationally fixed manner to an intermediate shaft 16 or is formed integrally therewith. The intermediate shaft 16 is arranged parallel to the input shaft 14. The transmission 13 has a planetary gear set PGS with a first element PI, second element P2, and third element P3, wherein the first element PI is connected to the primary drive machine ICE, the second element P2 is connected to the secondary drive machine EM, and the third element P3 is connected to the input shaft 14. In the first exemplary embodiment shown in Fig. 2, the primary drive machine ICE is drivingly connected to the first element PI of the planetary gear set PGS via a primary drive PD formed by a spur gear stage.

[0038] The transmission 13 has a gear pair arrangement 20 with four gear pairs L / l, 2, 3, 4, wherein each gear pair L / l, 2, 3, 4 has a fixed gear 1F, 2F, 3F, 4F and an idler gear 1L, 2L, 3L, 4L, which correspond to one another and mesh with one another. Fixed gears are gears that are rotationally fixedly connected to the respective supporting shaft—for example, the input shaft 14 or the intermediate shaft 16. Idler gears are gears that are rotatably mounted on the supporting shaft—for example, the intermediate shaft 16 or the input shaft 14—and can be switchably connected to this shaft by means of shifting elements assigned to the idler gears. The idler gears 1L, 2L, 3L, 4L and the fixed gears 1F, 2F, 3F, 4F of each gear pair L / l, 2, 3, 4 are thus arranged on different supporting shafts, with the supporting shafts arranged parallel and spaced apart from each other in the transmission 13. The idler gears IL, 3L of the gear pairs L / l, 3 are rotatably mounted on the intermediate shaft 16.Two gears of two gear pairs L / l, 3, each formed by a fixed gear IF, 3F, are arranged on and rotationally fixed to the input shaft 14. The idler gears 2L, 4L of the gear pairs 2, 4 are rotatably arranged on the input shaft 14. The fixed gears 2F, 4F of the gear pairs 2, 4 are arranged on and rotationally fixed to the intermediate shaft 16.

[0039] A first switching element CI, a second switching element C2 and a third switching element C3 are provided for carrying out gear changes.

[0040] Each of the switching elements CI, C2, C3, designed as a switching sleeve, has three switching positions in the first embodiment according to Fig. 2. These switching elements CI, C2, C3 are designed as double switching sleeves and additionally have a neutral position N between the two switching positions.

[0041] In the first switching position L - the left switching position in Fig. 2 - the switching element CI blocks the primary drive motor ICE by establishing a rotationally fixed connection with the housing H and, in this function, forms the switching element CIL assigned to the primary drive motor ICE. In the second switching position R - the right one in Fig. 2 - the first element PI and the third element P3 of the planetary gear set PGS are rotationally fixedly coupled to one another. Through this switching, the switching element forms the switching element CI assigned to the planetary gear set PGS. In the neutral position N of the switching element CI shown in Fig. 2, both the rotationally fixed connection with the housing H and between the two elements PI and P3 are canceled.A combined switching element is shown which, in its left switching position, represents the function of the switching element CIL assigned to the primary drive machine ICE and, in its right switching position, represents the function of the switching element CI assigned to the planetary gear set PGS.

[0042] In the first embodiment shown in Fig. 2, the shifting element C2 assigned to the idler gears 2L and 4L serves to activate or deactivate the idler gears 2L and 4L of the gear pairs 2 and 4. The shift sleeve of the shifting element C2 assigned to the idler gears is fixedly connected to the fixed gear 3F of the gear pair 3 or is formed integrally with it. In the first shift position L of the shifting element C2 - the left one in Fig. 2 - the idler gear 2L is activated, i.e. connected in a rotationally fixed manner to the input shaft 14, and the idler gear 4L is deactivated, i.e. separated from the first input shaft 14. In the second shift position R of the shifting element C2 - the right one in Fig. 2 - the idler gear 4L is activated, i.e. connected in a rotationally fixed manner to the input shaft 14, and the idler gear 2L is deactivated, i.e. separated from the first input shaft 14. In the neutral position N of the switching element C2 shown in Fig. 2, both idler gears 2L and 4L are deactivated, i.e. they can rotate freely on the supporting input shaft 14.

[0043] The switching element C3 assigned to the idler gears 1L and 3L serves to activate or deactivate the idler gear 1L of the gear pair L / l and the idler gear 3L of the gear pair 3. In the first switching position L of the switching element C3 - on the left in Fig. 2 - the idler gear 3L is activated, i.e. connected in a rotationally fixed manner to the intermediate shaft 16, and the idler gear 1L is deactivated, i.e. separated from the intermediate shaft 16. In the second switching position R of the switching element C3 - on the right in Fig. 2 - the idler gear 1L is activated, i.e. connected in a rotationally fixed manner to the intermediate shaft 16, and the idler gear 3L is deactivated, i.e. separated from the intermediate shaft 16. In the neutral position N of the switching element C3, both idler gears 1L and 3L are deactivated, i.e. can rotate freely on the supporting intermediate shaft 16.

[0044] In all embodiments shown in Fig. 2 to 6, the first element PI of the planetary gear set PGS is designed as a ring gear, the second element P2 of the planetary gear set PGS as a sun gear, and the third element P3 of the planetary gear set PGS as a planet carrier. The following applies to the stationary gear ratio i: 0PGS of the planetary gear set PGS (i.e. with the carrier held in place): where zi is the number of teeth on the ring gear and z2 is the number of teeth on the sun gear. The negative sign results from the change in direction of rotation.

[0045] The transmission 13 has a total of five gears GL, Gl, G2, G3, and G4 for ICE or hybrid operation (mode). ICE or hybrid operation modes are operating modes of the drive unit 12 in which a motor vehicle is driven by the primary drive motor ICE alone or in combination by the primary drive motor ICE and the secondary drive motor EM. The primary drive motor ICE can be operated in four fixed gears Gl, G2, G3, and G4 with torque assistance from the secondary drive motor EM. A further "virtual" gear GL can be operated with the rotor of the electric motor forming the secondary drive motor EM electrically blocked or with its speed assistance. For ICE or hybrid operation, the gear shift from GL to Gl is torque-filled, i.e., without torque interruption. The other gear shifts occur with torque interruption.

[0046] Transmission 13 also has four gears E1, E2, E3, and E4 for EV (electric mode). EV modes are operating modes in which a motor vehicle is powered solely by the secondary drive motor EM. This means that the vehicle is driven entirely by electricity. Gear shifts in EV mode occur with torque interruption.

[0047] The primary drive motor ICE can be started by the secondary drive motor EM when the vehicle is stationary or during electric travel, with the necessary torque being transmitted to the housing via a switching element 0WC1 assigned to the input shaft 14. This switching element 0WC1, for example a freewheel, is designed in such a way that rotation in one direction is possible and blocked in the opposite direction. The switching element 0WC1 is designed as a non-controllable one-way clutch. The switching element 0WC1 assigned to the input shaft 14 is arranged coaxially on the input shaft 14. This prevents the input shaft 14 from rotating in a direction associated with reversing the vehicle. When the vehicle is stationary, the primary drive motor ICE can be towed cold—i.e., unfired.Warm - i.e. fired - towing of the primary drive engine ICE can also take place when the vehicle is stationary or when the vehicle is coasting.

[0048] Furthermore, when stationary, it is possible to operate the secondary machine EM, which is designed as an electric machine, as a generator by the primary drive machine ICE – for example, to charge the vehicle battery SC. Advantageously, the transmission 13 has a fully progressive gear ratio. The ratios of the gears GL and Gl are identical and are each formed by the same gear pair L / l.

[0049] The four gear pairs L / l, 2, 3, 4 are arranged in four parallel gear planes e x , e2, £3, £4 of the gear 13.

[0050] The three shift elements C1, C2, and C3 can advantageously be designed as simple claw clutches with shift sleeves. This advantageously allows transmission 13 to operate entirely without friction clutches.

[0051] Advantageously, the switching element CI additionally has a special design to increase functional reliability. The geometry of this design is shown in the bottom right of Figs. 2 to 6. One flank of the switching element CI is beveled at a specific angle. The functional safety feature of this design is provided by the fact that in the event of a control failure, the secondary drive machine EM is deactivated and the braking torque acts on the inclined thrust flanks SF (design as shown in Figs. 2, 3 and 6) or the inclined drive flanks AF (design as shown in Figs. 4 and 5), whereby the switching element CI opens automatically and an unwanted braking effect is prevented. Especially for single-track motor vehicles, in particular motorcycles 11, this safety feature can prevent loss of control in most critical cases.Such a geometric and functional design of the switching element CI is generally referred to as a “functionally reliable switching element” within the meaning of the invention.

[0052] When the switching element CI is designed as a functional safety element, the torque applied by the secondary drive motor EM during ferry operation should not exceed a certain ratio to the torque of the primary drive motor ICE (described in equation 2) so that the drive flanks AF (design as shown in Figs. 2, 3, and 6) or the thrust flanks SF (design as shown in Figs. 4 and 5) remain loaded. This safety design of the switching element CI prevents pure ferry operation with the secondary drive motor EM while the primary drive motor ICE is idling. To achieve this, the primary drive motor ICE must be switched to pure electric mode while the primary drive motor ICE is stationary.

[0053] When the switching element CI is designed as a functional safety element, the torque applied by the secondary drive machine EM during regenerative braking should exceed a certain ratio to the torque of the primary drive machine ICE (described according to equation 2) so that the drive flanks AF (design as shown in Figs. 2, 3, and 6) or the thrust flanks SF (design as shown in Figs. 4 and 5) remain loaded. With this safety design of the switching element CI, braking with the primary drive machine ICE is not possible while the secondary drive machine EM is idling, for example, due to a fully charged battery. Other braking devices must be used for this purpose.

[0054] In equation 2, T £M the torque of the secondary drive machine EM, with T ;c£ the torque of the primary drive machine ICE, with i O p Gs is the stationary ratio of the planetary gear set PGS and i PD the ratio of the primary drive PD:

[0055] Figs. 2, 3, 4, 5, and 6 show embodiments of drive units 12 according to the invention, which are particularly suitable for single-track motor vehicles—in particular, motorcycles 11. When using the drive unit 12 for a single-track motor vehicle, a parking lock device and a reverse gear can generally be dispensed with.

[0056] In Fig. 2, 3, 4, 5 and 6, the secondary drive machine EM is arranged coaxially with the planetary gear set PGS.

[0057] In the embodiments shown in Figs. 2 to 6, the gears of the gear arrangement 20, at least of gear pairs 3 and 4, are straight-toothed. This makes it possible to form the switching element C2 and the switching element C3 each by an axially displaceable switching sleeve unit, wherein the switching element C2 is firmly connected to the adjacent fixed gear 3F of the adjacent gear pair 3, and the switching element C3 is firmly connected to the adjacent fixed gear 4F of the adjacent gear pair 4, for example, formed integrally therewith.

[0058] In the embodiments shown in Figs. 2 to 6, the planetary gear set PGS is arranged between the gear pair arrangement 20 and the secondary drive machine EM. The primary drive machine ICE is drivingly connected to the first element PI of the planetary gear set PGS via a primary drive PD, formed, for example, by a gear stage, and a torsional vibration damper D. All gears are advantageously designed with straight teeth, so that no axial forces occur.

[0059] The input shaft 14 is rotationally fixedly connected to the third element P3 of the planetary gear set PGS, formed by a planetary carrier. The shifting element CI assigned to the planetary gear set PGS in the first and second embodiments shown in Figs. 2 and 3 locks the planetary gear set PGS in the second shift position R shown on the right in Figs. 2 and 3 by rotationally fixedly connecting the first element PI—here formed as a ring gear—to the third element P3.

[0060] In the first embodiment shown in Fig. 2, the transmission 13 has the following switching pattern:

[0061] Stationary modes:

[0062] In the first embodiment shown in Fig. 2, reversing is prevented by 0WC1 during the electric modes E1, E2, E3, and E4. Likewise, the torque of the secondary drive motor EM during the ICE and hybrid modes G1, G2, G3, and G4 should not exceed a certain proportion of the torque of the primary drive motor ICE in ferry operation if the shifting element CI assigned to the planetary gear set is designed as a functionally reliable shifting element in its right-hand shift position R, as also shown in Figs. 2-6.

[0063] Transient modes:

[0064] Abbreviations in the switching table mean:

[0065] L Shift to the left

[0066] R Shift to the right

[0067] X activated

[0068] N neutral gear

[0069] SC Charging the vehicle battery

[0070] First gear in EV mode

[0071] E2 second gear in EV mode

[0072] E3 third gear in EV mode

[0073] E4 fourth gear in EV mode

[0074] GL "starting" gear in ICE and hybrid mode

[0075] Gl first gear in ICE and hybrid mode

[0076] G2 second gear in ICE and hybrid mode

[0077] G3 third gear in ICE and hybrid mode

[0078] G4 fourth gear in ICE and hybrid mode In the second embodiment shown in Fig. 3, the gear pair arrangement 20 corresponds to that of the first embodiment. The shift elements C2 and C3 are also designed as double shift sleeves. In the first shift element CI, the left shift position L, which in the first embodiment according to Fig. 2 provides support on the housing H, is omitted. In the second embodiment shown in Fig. 3, this support on the housing H is provided by another shift element OWC2 assigned to the primary drive machine ICE. This shift element OWC2, for example a freewheel, is designed such that rotation in one direction is possible, while the opposite direction is blocked. The shift element OWC2 is designed as a non-controllable one-way clutch.The OWC2 switching element assigned to the primary drive motor ICE is located on the shaft of the primary drive motor ICE (primary drive shaft), preventing the primary drive motor ICE from rotating in the opposite direction to its drive direction. Regenerative braking when driving with only the secondary drive motor EM is limited in this design variant, but is acceptable due to dynamic wheel load distribution and the resulting reduction in load on the rear wheel on single-track motorcycles.

[0079] Fig. 4 shows a variation of the second embodiment as a third embodiment, wherein the shifting element OWC1 assigned to the input shaft 14 is arranged inwardly between the gear pair arrangement 20 and the planetary gear set PGS, and the shifting element CI assigned to the planetary gear set PGS is arranged on the outside of the secondary drive machine EM and is designed in such a way that, when activated, locks the planetary gear set PGS by connecting the second element P2 - here formed as a sun gear - to the third element P3 in a rotationally fixed manner. The design of the shifting element CI can advantageously be as a functionally reliable shifting element. The associated geometric configuration is shown in Fig. 4 bottom right.The actuation and positioning of the shifting elements C2 and C3 takes place via a single shifting unit 30, which is advantageously designed as a shift drum that is actuated by a drive element 31, for example an electric motor. The design of the shifting unit 30 with the associated positions is shown in Fig. 7. Fig. 5 shows a fourth embodiment, a variation of the third embodiment, wherein the shifting element 0WC1 assigned to the input shaft 14 and the shifting element 0WC2 assigned to the primary drive machine ICE are arranged inside between the gear pair arrangement 20 and the planetary gear set PGS on the input shaft 14, and the shifting element CI assigned to the planetary gear set PGS is arranged on the outside of the secondary drive machine EM and is designed in such a way that, when actuated, locks the planetary gear set PGS by the second element P2 - here formed as a sun gear - being connected in a rotationally fixed manner to the third element P3.The design of the switching element CI assigned to the planetary gear set PGS can also be implemented as a functionally reliable switching element and is also shown in Fig. 5. The actuation and positioning of the switching elements C2 and C3 is also carried out via a single switching unit 30, which is actuated via a drive element 31. The design of the switching unit 30 with the associated positions is shown in Fig. 7.

[0080] The transmission 13 has the following switching pattern in the second, third and fourth embodiments shown in Fig. 3 - 5:

[0081] Stationary modes:

[0082] In the second, third, and fourth embodiments shown in Figs. 3-5, reversing during modes E1, E2, E3, and E4 is prevented by the shifting element OWC1 assigned to the input shaft 14. The shifting element OWC2 assigned to the primary drive motor ICE prevents the primary drive motor ICE from rotating backward during electric travel. Regenerative braking during modes E1, E2, E3, and E4 is limited by the breakaway torque of the primary drive motor ICE. Likewise, the torque of the secondary drive motor EM during the ICE and hybrid modes G1, G2, G3, and G4 should not exceed a certain proportion of the torque of the primary drive motor ICE in cruising mode if the shifting element CI assigned to the planetary gear set is designed as a functionally reliable shifting element in its right-hand shift position R, as also shown in Figs. 2-6.

[0083] Transient modes:

[0084] Notes on the transient mode “Start”:

[0085] The nearest neutral gear N must be engaged in electric mode

[0086] Remarks on the transient mode “ICE arrival”:

[0087] Battery charging during the start-up process. 0WC1 enables hill start assist.

[0088] Remarks on the transient mode “50% torque-filled GL-Gl switching”:

[0089] Battery discharge for active torque replenishment.

[0090] Abbreviations in the switching table mean:

[0091] L Shift to the left

[0092] R Shift to the right X activated

[0093] P Position of the switching unit 30 shown in Fig. 7

[0094] N neutral gear

[0095] SC Charging the vehicle battery

[0096] First gear in EV mode

[0097] E2 second gear in EV mode

[0098] E3 third gear in EV mode

[0099] E4 fourth gear in EV mode

[0100] GL "starting" gear in ICE and hybrid mode

[0101] Gl first gear in ICE and hybrid mode

[0102] G2 second gear in ICE and hybrid mode

[0103] G3 third gear in ICE and hybrid mode

[0104] G4 fourth gear in ICE and hybrid mode

[0105] Fig. 6 shows a fifth embodiment, a variation of the second embodiment, wherein the shifting element OWC1 assigned to the input shaft 14 is omitted and the shifting element CI in the left shift position L takes over the function of the shifting element assigned to the input shaft 14 and connects the input shaft 14 to the housing H in a rotationally fixed manner. The shifting element CI can also be designed as a functionally reliable shifting element and is also shown in Fig. 6 bottom right. Reversing with the secondary drive machine EM is possible in this fifth embodiment. The fifth embodiment according to Fig. 6 therefore shows - analogously to the first embodiment according to Fig. 2 - a combined shifting element which, in its left shift position, represents the function of the shifting element CIL assigned to the input shaft 14 and, in its right shift position, represents the function of the shifting element CI assigned to the planetary gear set PGS.In addition, the switching element has a neutral position N.

[0106] In the fifth embodiment shown in Fig. 6, the transmission 13 has the following switching pattern:

[0107] Stationary modes:

[0108]

[0109] In the fifth embodiment shown in Fig. 6, reversing and regenerative braking during modes E1, E2, E3, and E4 are limited by the breakaway torque of the primary drive motor ICE. Likewise, the torque of the secondary drive motor EM during the ICE and hybrid modes G1, G2, G3, and G4 should not exceed a certain proportion of the torque of the primary drive motor ICE in ferry operation if the shifting element CI assigned to the planetary gear set is designed as a functionally reliable shifting element in its right-hand shift position R, as also shown in Figs. 2 - 6.

[0110] Transient modes:

[0111] Abbreviations in the shift table mean: L Shift to the left

[0112] R Shift to the right

[0113] X activated

[0114] P Position of the switching unit 30 shown in Fig. 7

[0115] N neutral gear

[0116] SC Charging the vehicle battery

[0117] First gear in EV mode

[0118] E2 second gear in EV mode

[0119] E3 third gear in EV mode

[0120] E4 fourth gear in EV mode

[0121] GL "starting" gear in ICE and hybrid mode

[0122] Gl first gear in ICE and hybrid mode

[0123] G2 second gear in ICE and hybrid mode

[0124] G3 third gear in ICE and hybrid mode

[0125] G4 fourth gear in ICE and hybrid mode

[0126] In its design as a shift drum, as shown in Fig. 7 as a developed view, the shift unit 30 has seven defined rotational positions D1, D2, D3, D4, D5, D6, D7. To avoid switching errors as much as possible, it is advantageous if the rotational positions D1, D2, D3, D4, D5, D6, D7 of the shift drum are defined by a positioning device 40 with a spring-loaded locking element 41. For each rotational position D1, D2, D3, D4, D5, D6, D7, the shift drum has a position indicator 42 formed by a depression or recess - for example a notch - in the end face or outer surface of the shift drum. The locking element 41 engages positively with the position indicators 42 and ensures that the respective desired rotational position D1, D2, D3, D4, D5, D6, D7 of the shift drum can be precisely approached.

[0127] Fig. 8 shows a state diagram of a method according to the invention for starting a primary drive machine. In this specific embodiment, an internal combustion engine ICE is started by an electric machine EM as the secondary drive machine. The states over time of the method are shown on the x-axis of both diagrams, from left to right. The upper diagram shows the speed and torque curves of the various components, while the lower diagram shows the power and required tractive force curves. For the method according to the invention, the qualitative curve is primarily decisive, with the quantitative data representing a preferred solution in the exemplary embodiment shown.

[0128] The following sizes are shown in the diagram above:

[0129] - “Primary shaft speed”: speed of an input shaft 14,

[0130] - “ICE speed”: speed of a primary drive machine ICE,

[0131] - “EM speed”: speed of a secondary drive machine EM,

[0132] - “ICE torque”: torque of a primary drive machine ICE,

[0133] - “EM torque”: torque of a secondary drive machine EM, and

[0134] - “Vehicle speed”: (constant) speed of a motor vehicle.

[0135] The following sizes are shown in the diagram below:

[0136] - “ICE power”: power of the primary drive engine ICE,

[0137] - “EM power”: power of the secondary drive machine EM,

[0138] - “Total output power”: total output power of the drive unit, and

[0139] - "tractive effort": required pulling force.

[0140] The successive phases of the method according to the invention for starting the primary drive engine ICE are described in more detail in Figs. 9 to 14, based on the third embodiment shown in Fig. 4, in individual steps with the respective components involved. In the example described, the shift is made from fourth gear in electric mode E4 to third gear in ICE and hybrid mode G3. The steps can be applied analogously to other gear changes from electric mode to ICE and hybrid mode, to the other embodiments, and fundamentally to the drive unit according to the invention.

[0141] Fig. 9 shows a state of the drive unit 12, which describes the first step of the inventive method for starting a primary drive motor ICE. The elements and connections involved are shown in bold in the schematic representation. At the beginning of the first step (at point "E4 driving, OWC2 lock" in Fig. 8), the vehicle is in a driving mode in which the entire required driving power is provided by the secondary drive motor EM or is braked regeneratively. The secondary drive motor EM rotates in the positive direction (forward). The primary drive motor ICE is switched off and, when driven, is blocked from rotating backward via the one-way switching element OWC2.In the case of regenerative braking, the static breakaway torque of the primary drive motor ICE provides the necessary support torque and thus also determines a limit for the maximum braking torque that can be applied via the secondary drive motor EM. In the present example, fourth gear E4 is engaged in electric mode. However, for the method according to the invention, all other gears can also be engaged in electric mode as a starting point. The shift element C2 is in the right shift position and connects the idler gear 4L in a rotationally fixed manner to the input shaft 14, and the shift element C3 is in the neutral position. In the first step, between the points "E4 driving, OWC2 lock" and "C2R disengagement" shown on the x-axis according to Fig. 8, the torque of the secondary drive motor EM is reduced in order to relieve the load on the shift element C2. Furthermore, Fig.9 The lower right area shows the speed and force relationships of the planetary gear set PGS. The largest circle represents the ring gear, i.e., the first element PI, the smaller lower circle the sun gear, i.e., the second element, and the smaller upper circle the planet carrier including the planet, i.e., the third element of the planetary gear set PGS. The first element PI is rotationally connected to the switching element 0WC2. In the state shown, the first element PI, blocked by the switching element 0WC2, does not rotate, which is indicated by an "X" in the left-hand illustration. Its speed is therefore zero. The second element P2 is driven by the secondary drive machine EM and has the speed indicated by the lower right-pointing arrow. This results in the speed at the third element P3, indicated by the smaller right-pointing arrow. The acting forces are shown in the right-hand illustration.Here, the force applied by the secondary drive machine EM, represented by the lower arrow pointing to the right, leads to the forces represented by the three other arrows on the third member of the planetary gear set PGS.

[0142] Fig. 10 shows a state of the drive unit 12 during the second and third steps of the method according to the invention. In the second step (at the point "C2R disengagement" in Fig. 8), the shift element C2 is shifted from the right shift position R to the middle neutral position, so that the transmission 13 is in a neutral position without a gear engaged. In the subsequent third step (from the point "C2R disengagement" up to and including the point "EM stop" in Fig. 8), the secondary drive motor EM is controlled such that the speed of the secondary drive motor EM decreases to a standstill. According to the speed and force relationships shown in the lower right area of ​​Fig. 10, at the end of the third step, all three elements of the planetary gear set PGS are stationary and no forces are transmitted.The motor vehicle is in sailing mode, which means that no power or torque is transmitted from the drive unit 12 to the wheels.

[0143] Fig. 11 shows a state of the drive unit 12 during the fourth and fifth steps of the method according to the invention. In the fourth step (from the point "EM stop" to "Cranking" in Fig. 8), the secondary drive machine EM is subjected to a torque in the opposite (negative) direction, wherein the input shaft 14 is blocked by the one-way shift element OWC1 as the shift element assigned to the input shaft 14, so that the third element P3 of the planetary gear set PGS absorbs a reaction torque. At the time "OWC1 lock", the shaft of the primary drive machine ICE is released from the blocked state via the first element PI, thus beginning to rotate forward. The speeds of the secondary drive machine EM and the primary drive machine ICE increase until the time "Cranking", in which the fifth step (from the time "Cranking" up to and including the time "ICE idle" according to Fig.8) the primary drive motor ICE is started; in the case of an internal combustion engine as the primary drive motor ICE, fuel injection and ignition occur. At the time "ICE idle," the primary drive motor ICE runs independently. The lower right area of ​​Fig. 11 shows the speed and force relationships in the planetary gear set PGS during the starting of the primary drive motor ICE, with the third element P3 being blocked by the switching element OWC1 (as the switching element assigned to the input shaft 14), the second element P2 being driven by the secondary drive motor EM, and the torque being transferred to the first element PI. The vehicle is in coasting mode, meaning no power or torque is transferred from the drive unit 12 to the wheels of the motor vehicle.

[0144] Fig. 12 shows a state of the drive unit 12 during the sixth and seventh steps according to claim 10 of the method according to the invention. In the sixth step (from the point "ICE idle" to "C3L engagement" in Fig. 8), the speed of the secondary drive machine EM is reduced (but initially remains in the negative direction), whereby the input shaft 14 is released from the blockage by the freewheel 0WC1 as the shifting element assigned to the input shaft 14. In the subsequent seventh step according to claim 10 (at the time "C3L engagement" according to Fig. 8), the speeds of the counter elements of the shifting element C3 to be engaged for the target gear G3 are synchronized by simultaneously controlling the speeds of the primary drive machine ICE and the secondary drive machine EM. The lower right area of ​​Fig. 12 shows the speed and force ratios that act in the planetary gear set PGS before the time "C3L engagement" according to Fig. 8.The planetary gear set PGS is freely movable, i.e., not locked, and without force. The vehicle is in coasting mode, meaning no power or torque is transferred from the drive unit 12 to the vehicle's wheels.

[0145] Fig. 13 shows a state of the drive unit 12 during the eighth and ninth steps of the method according to the invention according to claim 10. In the eighth step (at the time "C3L engagement" in Fig. 8), the shift element C3 to be engaged for the target gear G3 is shifted from the middle neutral position to the left into the shift position L, so that the transmission 13 is in third gear in the ICE and hybrid mode G3. In the subsequent ninth step (from the time "C3L engagement" to "CI engagement" according to Fig. 8), a torque is applied simultaneously by the primary drive motor ICE and the secondary drive motor EM, whereby the torques on the first and second elements P1, P2 of the planetary gear set PGS balance each other out. The lower right area in Fig. 13 shows the speed and force ratios that act in the planetary gear set PGS before the time "CI engagement" according to Fig. 8.This demonstrates the balance of forces and the consistent direction of rotation of all elements of the planetary gear set (PGS). The vehicle can now be driven in hybrid mode via the primary drive motor (ICE) and the secondary drive motor (EM).

[0146] Fig. 14 shows a state of the drive unit 12 during the eleventh and twelfth

[0147] Step of the inventive method according to claim 11. In the tenth

[0148] In the 1st step (shortly before the time "CI engagement" according to Fig. 8), the speeds of the counter elements of the shift element CI to be engaged for the target gear G3 are synchronized by simultaneously controlling the speeds of the primary drive motor ICE and the secondary drive motor EM. In the subsequent twelfth step according to claim 11 (at the time "CI engagement" in Fig. 8), the shift element CI to be engaged for the target gear G3 is actuated and the planetary gear set PGS is locked against rotation. In the specific embodiment, the second P2 and third P3 elements of the planetary gear set PGS are connected to one another in a rotationally fixed manner, thereby blocking the planetary gear set PGS. In one embodiment, this can also be achieved by connecting the first P1 and third P3 elements. In the twelfth step (from the time "CI engagement" to the time "G3-boost" according to Fig.8), a torque is applied by at least the primary drive motor ICE or the secondary drive motor EM. The vehicle is now driven in hybrid mode via both drive elements, i.e., the primary drive motor ICE and the secondary drive motor EM. The vehicle can accordingly be driven in ICE mode (only by the primary drive motor ICE) or in hybrid mode (by the primary drive motor ICE and the secondary drive motor EM). The lower right area of ​​Fig. 14 shows the speed and force relationships that act in the planetary gear set PGS at the time "G3-boost" according to Fig. 8. The speed representation indicates a rotationally fixed connection between the second P2 and third P3 elements of the planetary gear set PGS. The elements of the interlocked planetary gear set PGS all rotate in the same direction.The forces shown, acting to the right in the planes between the first PI and third P3 elements, and between the second P2 and third P3 elements, represent the forces acting from the first PI element and the second P2 element on the third P3 element due to the drive torques of the primary drive motor ICE and the secondary drive motor EM. The force acting to the right, acting at the center of the third P3 element, is the resultant force of these two elements. The forces acting to the left in the same planes (P1,P3 and P2,P3) represent the forces resulting from the third P3 element on the first PI element and the second P2 element (action equals reaction).

Claims

PATENT CLAIMS Drive unit (12) for a motor vehicle, in particular for a motorcycle (11), with a primary drive machine (ICE), a secondary drive machine (EM) and a transmission (13), wherein the drive unit (12) comprises: • an input shaft (14); • an output shaft (17); • an intermediate shaft (16) arranged parallel to the input shaft (14) and connected to the output shaft (17); • a planetary gear set (PGS) with a first (PI), second (P2) and third member (P3), wherein the first member (PI) is rotationally connected to the primary drive machine (ICE), the second member (P2) is rotationally connected to the secondary drive machine (EM) and the third member (P3) is rotationally connected to the input shaft (14); • a switching element (CI) assigned to the planetary gear set (PGS), which is designed to connect two elements (P1, P3 or P2, P3) of the planetary gear set (PGS) to one another in a rotationally fixed manner in a first switching position; • a gear pair arrangement (20) with several gear pairs (L / l, 2, 3, 4), each gear pair having a fixed gear (1F, 2F, 3F 4F) and a loose gear (1L, 2L, 3L, 4L), each loose gear (1L, 2L, 3L, 4L) being able to be activated or deactivated via a switching element (C2, C3) assigned to the loose gear, • the idler gears (1L, 2L, 3L, 4L) of at least two gear pairs (L / l, 2, 3, 4) are rotatably mounted on the intermediate shaft (16), and the fixed gears (1F, 2F, 3F, 4F) of these at least two gear pairs (L / l, 2, 3, 4) are arranged in a rotationally fixed manner on the input shaft (14), • a switching element (OWC1, CIL) associated with the input shaft (14) for blocking the input shaft (14) against rotation in at least one direction of rotation, and • a switching element (CIL, OWC2) assigned to the primary drive machine (ICE) for blocking the primary drive machine (ICE) against rotation in at least one direction of rotation. Drive unit (12) according to claim 1, characterized in that the switching element (OWC1) assigned to the input shaft (14) is designed as a non-controllable freewheel, which is arranged such that it prevents rotation the input shaft (14) is blocked in a direction of rotation associated with reverse travel of the motor vehicle. Drive unit (12) according to claim 1, characterized in that the shifting element (CIL) associated with the input shaft (14) is designed as a controllable claw brake, which is arranged such that it blocks rotation of the input shaft (14) in both directions of rotation and is designed in particular in combination with the shifting element (C1R) associated with the planetary gear set (PGS) and blocks the planetary gear set (PGS) in a shift position. Drive unit (12) according to one of claims 1 to 3, characterized in that the shifting element (0WC2) associated with the primary drive machine (ICE) is designed as a non-controllable one-way clutch, which is arranged such that it blocks rotation of the primary drive machine (ICE) counter to the drive direction of the primary drive machine (ICE).Drive unit (12) according to one of claims 1 to 3, characterized in that the shifting element (CIL) assigned to the primary drive motor (ICE) is designed as a controllable claw brake that blocks rotation of the primary drive motor (ICE) in both directions of rotation, wherein the controllable claw brake (CIL) is combined with the shifting element (C1R) assigned to the planetary gear set (PGS) and blocks the planetary gear set (PGS) in a shift position. Drive unit (12) according to one of the preceding claims, characterized in that the shifting element (0WC2) assigned to the primary drive motor (ICE) is arranged on the shaft of the primary drive motor (ICE).Drive unit (12) according to one of claims 1 to 5, characterized in that the axis of rotation of the primary drive machine (ICE) is arranged offset parallel to the input shaft (14) and is connected via a primary drive (PD) to the first member (PI) of the planetary gear train (PGS), wherein in particular the switching element (0WC2, CIL) assigned to the primary drive machine (ICE) is used to block the. Primary drive machine (ICE) is arranged on the driven member of the primary drive (PD) coaxially to the input shaft (14). Drive unit (12) according to one of the preceding claims, characterized in that the first member (PI) of the planetary gear set (PGS) is designed as a ring gear, the second member (P2) of the planetary gear set (PGS) is designed as a sun gear, and the third member (P3) of the planetary gear set (PGS) is designed as a planet carrier.Drive unit (12) according to one of the preceding claims, characterized in that the shifting element (CI) assigned to the planetary gear set (PGS) is designed as a functionally reliable shifting element, i.e. has a geometry in which a first flank (AF, SF) is designed at right angles to the direction of rotation of the shifting element (CI) and a second flank (SF, AF) of the shifting element (CI) is beveled at a specific angle to the direction of rotation of the shifting element (CI), whereby the functionally reliable shifting element (CI) opens automatically when a braking torque is applied by the secondary drive machine (EM). Motor vehicle, in particular motorcycle, with a drive unit (12) according to one of the preceding claims.Method for starting a primary drive machine (ICE), in particular an internal combustion engine, during an electric driving mode of a drive unit, in particular a drive unit according to one of claims 1 to 9, comprising the following steps:. 1) Reduction of the torque of a secondary drive machine (EM) in an electric mode (El, E2, E3, E4), in which the secondary drive machine (EM) rotates forward and a gear pair (L / l, 2, 3, 4) of a transmission (13) is engaged by at least one shifting element (C2, C3) associated with a loose wheel of a gear pair, wherein the primary drive machine (ICE) is blocked by a shifting element (CIL, OWC2) associated with the primary drive machine (ICE) and the secondary drive machine (EM) is disengaged via a planetary gear set (PGS) and the switched gear pair (4) delivers power to a driven output shaft; ) Opening of at least one switching element (C2) assigned to an idler gear of a gear pair, so that the idler gear (4L) of the switched gear pair (4) is separated from the supporting shaft; ) Reduction of the speed of the secondary drive machine (EM) by its own controllable braking torque until the secondary drive machine (EM) comes to a standstill;) Rotating the secondary drive machine (EM) in the opposite direction, wherein the input shaft (14) is blocked by a switching element (0WC1, CIL) assigned to the input shaft (14), so that the third member (P3) of the planetary gear set (PGS) absorbs a reaction torque and the shaft of the primary drive machine (ICE) is released from the blocking by means of the first member (PI) of the planetary gear set (PGS) or releasing the primary drive machine (ICE) by the switching element (CIL) assigned to the primary drive machine (ICE) during steps 2 to 4, and is rotated forward; ) Starting the primary drive machine (ICE) as soon as its speed has reached the starting speed;) Reduction of the speed of the secondary drive machine (EM), whereby the input shaft (14) is released from the blockage by the switching element (0WC1) assigned to the input shaft (14) or releasing the input shaft (14) by the switching element (CIL) assigned to the input shaft (14) during step 5 or 6. en according to claim 11, which has the following further steps: ) Synchronizing the speeds of the counter elements of a first switching element (C3) to be closed for the target gear by controlling the; Speeds of the primary drive motor (ICE) and the secondary drive motor (EM); ) Closing the first shift element (C3) to be closed for the target gear; ) Applying a torque by the primary drive motor (ICE) and the secondary drive motor (EM), wherein the torques on the first and second elements (Pl, P2) of the planetary gear set (PGS) balance each other out.en according to claim 12, which has the following further steps: ) Synchronizing the speeds of the counter-elements of a second shift element (CI) to be closed for the target gear by controlling the speeds of the primary drive machine (ICE) and the secondary drive machine (EM); ) Closing the second shift element (CI) to be closed for the target gear; ) Providing a torque by at least the primary drive machine (ICE) or the secondary drive machine (EM). en according to claim 10, which has the following further steps: ) Synchronizing the speeds of the counter-elements of a first shift element (CI) to be closed for the target gear by controlling the speeds of the primary drive machine (ICE) and the secondary drive machine (EM); ) Closing the first shift element (CI) to be closed for the target gear; ) Synchronizing the speeds of the counter-elements of a second shift element (C3) to be closed for the target gear by control. the speeds of the primary drive machine (ICE) and the secondary drive machine (EM) 10) Closing the second switching element (C3) to be closed for the target gear; 11) Providing torque by at least the primary drive motor (ICE) or the secondary drive motor (EM). The method according to claim 10, comprising the following further steps: 7) Synchronising the speeds of the counter-elements of the switching elements (CI, C2, C3) to be closed for the target gear by controlling the speeds of the primary drive motor (ICE) and the secondary drive motor (EM); 8) Closing, in particular simultaneous closing, of the switching elements (CI, C2, C3) to be closed for the target gear; 9) Provision of a torque by at least the primary drive machine (ICE) or the secondary drive machine (EM). Method according to one of claims 10 to 15, characterized in that the switching element (OWC2) assigned to the primary drive machine (ICE) is designed as a freewheel and the primary drive machine (ICE) is blocked against rotation in the reverse direction by the freewheel in step 1 and is released in step 4 as soon as the torque of the secondary drive machine (EM) exceeds the breakaway torque of the primary drive machine (ICE) in the forward direction. Method according to one of claims 10 to 16, characterized in that the maximum torque of the secondary drive machine (EM) in regenerative braking mode is limited in step 1 to a value such that breakaway of the primary drive machine (ICE) is not caused. Method according to one of claims 10 to 17, characterized in that the switching element (0WC1) assigned to the input shaft (14) is designed as a freewheel and the input shaft (14) is blocked against rotation in the reverse direction by the freewheel in step 4 and is released in step 6 as soon as the speed of the input shaft (14) is reduced.

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