Hybrid Transmission Unit and Motor Vehicle

Abstract

A hybrid transmission device (3) includes at least one electric motor (EM1, EM2), a first transmission input shaft (7), and a second transmission input shaft (9) mounted on the first transmission input shaft (7). A connecting clutch (K3) is configured for rotationally fixedly connecting the first transmission input shaft (7) and the second transmission input shaft (9). The second transmission input shaft (9) includes an end (11) facing toward the outer side of the hybrid transmission device (3) and an end (13) facing toward the inner side of the hybrid transmission device (3). The connecting clutch (K3) is arranged at the end (13) of the second transmission input shaft (9) facing toward the inner side of the hybrid transmission device (3).

Claims

1-15. (canceled)

16. A hybrid transmission device (3) with a transmission (4), comprising: a first transmission input shaft (7); a second transmission input shaft (9) mounted on the first transmission input shaft (7); at least one countershaft (22); and at least one drive device (EM2) associated with the second transmission input shaft (9), wherein fixed gears (10, 12), exclusively, are arranged on the second transmission input shaft (9).

17. The hybrid transmission device (3) of claim 16, further comprising a clutch (K1) for connecting the first transmission input shaft (7) to an internal combustion engine (2).

18. The hybrid transmission device (3) of claim 16, further comprising a clutch (K2) for connecting the second transmission input shaft (9) to an internal combustion engine (2).

19. The hybrid transmission device (3) of claim 16, further comprising a connecting clutch (K3) for connecting the first transmission input shaft (7) and the second transmission input shaft (9).

20. The hybrid transmission device (3) of claim 16, further comprising a plurality of clutches (K1, K2, K3) and a plurality of gearshift clutches (A, B, C, D, E, F), wherein one or more of the clutches (K1, K2, K3) and the gearshift clutches (A, B, C, D, E, F) is a dog clutch.

21. The hybrid transmission device (3) of claim 16, wherein a first one of the at least one drive device (EM1, EM2) is associated with the first transmission input shaft (7), and a second one of the at least one drive device (EM1, EM2) is associated with the second transmission input shaft (9).

22. The hybrid transmission device (3) of claim 16, further comprising exactly four two-sided engagement devices (S1, S2, S3, S4) for producing five internal-combustion-engine and/or electric forward gear steps (V1, V2, V3, V4, V5, E1, E2, E3, E4, E5).

23. The hybrid transmission device (3) of claim 16, further comprising a connecting clutch (K3) mounted on the first transmission input shaft (7).

24. The hybrid transmission device (3) of claim 16, further comprising exactly two engagement devices (S1, S4) arranged on the first transmission input shaft (7).

25. The hybrid transmission device (3) of claim 16, further comprising exactly one countershaft (22).

26. The hybrid transmission device (3) of claim 25, further comprising exactly two engagement devices (S2, S3) arranged on the countershaft (22).

27. The hybrid transmission device (3) of claim 25, further comprising exactly one fixed gear for forming a forward gear step (G3) arranged on the countershaft (22).

28. The hybrid transmission device (3) of claim 16, wherein the at least one drive device (EM1, EM2) is attached at a gear-step fixed gear (10, 18).

29. The hybrid transmission device (3) of claim 16, wherein: at least one axially external gear-step gear (10, 18) is arranged on an axis (A1) of the first transmission input shaft (7); and the at least one of axially external gear-step gears (10, 18) is a fixed gear (10, 18).

30. A motor vehicle (1), comprising the hybrid transmission device (3) of claim 16.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0095] Further advantages, features, and details of the invention result from the following description of exemplary embodiments and figures, in which:

[0096] FIG. 1 shows a motor vehicle;

[0097] FIG. 2 shows a first gear set scheme;

[0098] FIG. 3 shows a circuit diagram;

[0099] FIG. 4 shows a first shift pattern;

[0100] FIG. 5 shows the hybrid transmission device in a side view;

[0101] FIG. 6 shows a circuit diagram for a crawler gear;

[0102] FIG. 7 shows a circuit diagram for a hybrid gear;

[0103] FIG. 8 shows a representation of a first gear change over time;

[0104] FIG. 9 shows a representation of a second gear change over time;

[0105] FIG. 10 shows a second gear set scheme;

[0106] FIG. 11 shows a second shift pattern; and

[0107] FIG. 12 shows a third gear set scheme.

DETAILED DESCRIPTION

[0108] Reference will now be made to embodiments of the invention, one or more examples of which are shown in the drawings. Each embodiment is provided by way of explanation of the invention, and not as a limitation of the invention. For example, features illustrated or described as part of one embodiment can be combined with another embodiment to yield still another embodiment. It is intended that the present invention include these and other modifications and variations to the embodiments described herein.

[0109] FIG. 1 shows a motor vehicle 1 with an internal combustion engine 2 and a hybrid transmission device 3. The hybrid transmission device 3 also includes, as described in greater detail further below, electric motors and a clutch device, and so the hybrid transmission device 3 can be installed as an assembly unit. This is not absolutely necessary, however. In principle, the gear set can form an assembly unit even without a previously connected clutch assembly and the electric motors. A control device 15 is provided for the open-loop control of the hybrid transmission device 3. This can be part of the hybrid transmission device 3 or of the motor vehicle 1.

[0110] FIG. 2 shows the hybrid transmission device 3 and, in particular, a gear change transmission 4 of the hybrid transmission device 3, in the form of a gear set scheme. In the following, the hybrid transmission device 3 will be described starting from the internal combustion engine 2. Two clutches K1 and K2 are attached, on the input-side, to a crankshaft 5. An output part 6 of the clutch K1 is connected to a first transmission input shaft 7 and an output part 8 of the clutch K2 is connected to a second transmission input shaft 9. Two fixed gears 10 and 12 are arranged on the second transmission input shaft 9. The fixed gear 10 is the fixed gear of the fourth gear step G4 and the fixed gear 12 is the fixed gear of the second gear step G2.

[0111] The second transmission input shaft has two ends, namely one end 11 pointing or facing toward the outer side of the hybrid transmission device 3 and one end 13 pointing or facing toward the inner side of the hybrid transmission device 3.

[0112] An engagement device S1, mounted on the transmission input shaft 7, with a clutch K3 and a gearshift clutch C follows. By the gearshift clutch C, an idler gear 14 can be rotationally fixed to the transmission input shaft 7. The idler gear 14 is the idler gear of the third gear step G3.

[0113] On the first transmission input shaft 7, the fixed gears 16 and 18 follow, wherein the fixed gear 16 is the fixed gear of the first gear step G1 and the fixed gear 18 is the fixed gear of the fifth gear step G5.

[0114] The second transmission input shaft 9 is therefore designed to be shift element-free and idler gear-free. Two engagement devices S1 and S4 are arranged on the first transmission input shaft 7. The engagement device S1 includes the clutch K3 and the gearshift clutch C and, therefore, is designed to be two-sided.

[0115] The axis of rotation of the first transmission input shaft 7 and of the second transmission input shaft 9 is labeled with A1.

[0116] The hybrid transmission device 3 includes a single countershaft 22 for connection to a differential 20 and to form the gear stages or gear steps. Two engagement devices S2 and S3 are arranged on the countershaft 22 with the gearshift clutches A, B, D, and E for connecting the idler gears 24, 26, 30, and 32 to the countershaft 22. As the only gear-implementing fixed gear, the fixed gear 34 is located between the idler gears 24, 26, 30, and 32 on the countershaft 22. The assignment to the gear steps results on the basis of the gear step numbers G1 through G5 below the gearwheels arranged on the countershaft 22. The fixed gear 36 is not a gear-implementing fixed gear. The fixed gear 36 connects the countershaft 22 to the differential 20 as a drive output constant. On the basis of this scheme, the following can be determined with respect to the forward gear steps:

[0117] One fixed gear and one idler gear are associated with each forward gear step and, in fact, a single fixed gear and a single idler gear in each case. Each fixed gear and idler gear are always unambiguously associated with a single forward gear step, i.e., there are no winding-path gears by utilizing one gearwheel for multiple gear steps. Nevertheless, the forward gear steps G2 and G4 can be considered to be coupling gears, since the first transmission input shaft 7 is interconnected during the formation of the forward gear steps G2 and G4.

[0118] The electric motors EM1 and EM2 are attached as shown and, in fact, at the axially external gearwheels 10 and 18. As a result, it is possible to attach the electric motors EM1 and EM2 without additional gearwheels on one of the transmission input shafts 7 and 9, as the result of which installation space is saved. In particular, due to the attachment of the electric motors EM1 and EM2 at the axially outermost gearwheels 10 and 18, an axially extremely short hybrid transmission device 3 can be created.

[0119] The electric motors EM1 and EM2 are arranged in parallel to the transmission input shaft 7 and the electric motors EM1 and EM2 output at opposite sides. This means, as shown in FIG. 2, the output and/or the output shaft 33 of the electric motor EM1 points or faces toward the end 35 of the gear change transmission 4 facing away from the motor and the output shaft 31 of the electric motor EM2 points or faces toward the end 37 of the gear change transmission 4 facing the motor. In FIG. 2, one end therefore points toward the left and one end points toward the right. The electric motors EM1 and EM2 are arranged partially overlapping in the axial direction, and so the hybrid transmission device 3, in the area of the electric motors EM1 and EM2, takes up only approximately the length occupied by a single electric motor. Due to the above-described arrangement of the shift elements S1, S2, S3, and S4 and the design of the reverse gear without a reversing gearwheel, a length of the hybrid transmission device 3 of slightly more than thirty centimeters (30 cm) is made possible.

[0120] FIG. 3 shows a circuit diagram of the hybrid transmission device 3 according to FIG. 2, from which the circuit diagram arises, for example, that the clutch K3 connects the input shafts 7 and 9 of the sub-transmissions 36 and 38. The sub-transmission 36 includes the odd gears and the sub-transmission 38 includes the even gears.

[0121] FIG. 4 shows a first shift pattern for the hybrid transmission device 3 according to FIG. 2, in which it is apparent that the clutch K1 can be engaged in all internal-combustion-engine gears V1 through V5. This also applies for the internal-combustion-engine forward gears V1 through V4 of the example embodiments described further below. In contrast to a typical dual clutch transmission, in which the clutches K1 and K2 are alternately disengaged and engaged during the shifting of the forward gears, the even internal-combustion-engine gears V2, V4 are achieved in that the clutches K1 and K3 are engaged. A changeover between the sub-transmissions therefore preferably takes place via the disengagement and engagement of the clutch K3. In contrast to typical dual clutch transmissions, the utilization of the clutches is therefore implemented in a deviating manner. As is already also apparent from FIG. 2, precisely one of the gearshift clutches A through E is engaged and in the power flow in each of the internal-combustion-engine forward gears.

[0122] The described hybrid transmission device 3 has several functional advantages. For example, due to the described arrangement, both electric motors can be operated as a motor and as a generator. As a result, it is possible, for example, to provide a crawler gear, which is entered as gear E1 in the shift pattern for the electric motor EM1. It has a ratio of over forty (40). For this purpose, the clutch K2 and the gearshift clutch A are engaged. Since the crawler gear produced with the hybrid transmission device 3 is formed via driving with the electric motor EM1, the electric motor EM2 can be utilized as a generator in the meantime. In the crawler gear E1, therefore, the electric motor EM1 is utilized as a motor and the electric motor EM2 is utilized as a generator.

[0123] This is also the sole utilization of the clutch K2.

[0124] Of course, the crawler gear E1 can also be operated in a battery electric manner. In this case, only the gearshift clutch A is necessarily engaged. K2 can be disengaged.

[0125] In each of the electric motor-operated forward gears E3 and E5, one of the gearshift clutches C or E is engaged, as the result of which the described ratios are produced. In these gears as well, it is possible to engage K2 and utilize EM2 as a generator.

[0126] With the electric motor EM2, two electric motor-operated forward gears E2 and E4 can also be produced. For this purpose, only the second transmission input shaft 9 and the shift element S2, with one of the clutches B or D in each case, are utilized. In two electric motor-operated forward gears E2 and E4 gears, it is possible, therefore, to engage K1 and utilize EM1 as a generator.

[0127] Via the two electric motors EM1 and EM2, five electric forward gears, including one crawler gear, can therefore be formed, wherein only one of the two sub-transmissions 36 or 38 must be integrated in each case.

[0128] The gearshift clutches A through E and at least the clutches K2 and K3 are advantageously designed as dog clutches. Preferably, the clutch K1 is also designed as a dog clutch. An internal-combustion-engine gear change under load takes place by utilization of the electric motors EM1 and/or EM2.

[0129] The gear change from the internal-combustion-engine gear V1 into the internal-combustion-engine gear V2 is described in the following. In the internal-combustion-engine forward gear V1, the clutch K1 and the gearshift clutch A are engaged. In addition, the gearshift clutch B can be engaged, but not yet loaded. Thereupon, the electric motor EM1 is operated as a generator in such a way that the cumulative torque of the internal combustion engine 2 and of the electric motor EM1 is approximately equal to zero (0), while the electric motor EM2 applies the torque at the drive output. The torque reduction or increase can take place linearly in each case. As a result, the gearshift clutch A becomes load-free and can be disengaged.

[0130] Thereafter, the electric motor EM1 and the internal combustion engine 2 synchronize the first transmission input shaft 7, via which no torque is transmitted in this moment, with respect to the second transmission input shaft 9, and so the clutch K3 can be engaged. Finally, a load change from the electric motor EM2 to the internal combustion engine 2 takes place, as the result of which the internal-combustion-engine forward gear V2 is achieved. In the internal-combustion-engine second forward gear V2, the gearshift clutch B is engaged. Therefore, the electric motor EM2 can be operated as a generator in this case, provided the gearshift clutch B is to be disengaged again.

[0131] FIG. 5 shows a side view of the transmission according to FIG. 2. The axes A4 and A5 of the electric motors EM1 and EM2 are arranged above and laterally with respect to the axis A1 of the first transmission input shaft 7 and also of the second transmission input shaft 9. The axis A2 of the countershaft 22 and the axis A3 of the differential are advantageously situated below the axis A1 of the first transmission input shaft 7. The axes A4 and A5 are arranged symmetrically with respect to the axis A1 in such a way that the distance of the axes A4 and A5 to the axis A1 is identical and the angle with respect to the perpendicular 60 is also identical.

[0132] FIG. 6 shows the hybrid transmission device 3 and the motor vehicle 1 as a circuit diagram in the crawler gear, wherein the electric motor EM1 is utilized not only as a main drive source, but rather even as the sole drive source of the motor vehicle 1. The gearshift clutch A is engaged. The first gear step G1 is therefore provided for transmitting torque to the drive output. Since the electric motor EM1 is the drive source, this is equivalent to the utilization of the electric gear E1. Due to the engagement of the clutch K2, the internal combustion engine 2 can drive the electric motor EM2. The electric motor EM2 is therefore operated as a generator and, in this way, can generate current for inching operations of longer duration. Neither the internal combustion engine 2 nor the electric motor EM2 are connected to the drive output in this case.

[0133] FIG. 7 shows a hybrid gear H22, in which the internal combustion engine and also the electric motor EM2 are connected to the drive output via the gear-step gears 12 and 26 of the second gear step G2. The clutch K3 is engaged in order to connect the internal combustion engine 2 to the gear-step gears 12 and 26. Due to the engaged clutch K1, the electric motor EM1 is also connected to the internal combustion engine 2 and can be operated as a generator, as necessary. A portion of the power of the internal combustion engine 2 can therefore be utilized for the operation of the electric motor EM1 as a generator and a portion can be output to the drive output of the hybrid transmission device 3.

[0134] The electric motor EM1 does not need to be continuously operated as a generator, as described. Rather, a change-over can be carried out between the electric motors EM1 and EM2.

[0135] With regard to the nomenclature, the first number of the hybrid gear designates the internal-combustion-engine gear and the second number designates an electric motor-operated gear. It is not expressed whether the first electric motor is operated as a motor or as a generator, for example, in the hybrid gear H32.

[0136] FIG. 8 shows a representation of a gear change from a hybrid gear H22 to H32 over time. A change-over from the internal-combustion-engine gear V2 to V3 is therefore carried out, while the electric-motor gear E2 remains.

[0137] Rotational speeds are represented in the upper section, engine/motor torques are represented in the middle section, and the output torque is represented in the lower section.

[0138] At the point in time to, a gear shift is present as shown in FIG. 7. The internal combustion engine 2 and the electric motor EM2 provide output via the gear-step gears of the second gear to the drive output. The engine/motor speed 41 of the internal combustion engine 2 and of the electric motor EM1 coupled thereto and the motor speed 42 of the electric motor EM2 are at initial values. Due to a request for a gear change, at the point in time t.sub.1, the engine torque of the internal combustion engine 2, which is represented in the curve 40, is reduced. Simultaneously, the electric motor EM1, the curve 43 of which therefore extends below zero (0), is operated as a generator. The initial values 44 and 46 are reduced to the target values 48 and 50 by the point in time t.sub.2.

[0139] In addition, at the point in time t.sub.1, the electric motor EM2 begins to ramp up, starting from the start value, to a target value 52. The motor torque of the electric motor EM2 is represented in the curve 54. If the target values 48 and 50 are selected in such a way that the target values 48 and 50 have the same amount, this means the cumulative torque of the internal combustion engine 2 and the electric motor EM1 is equal to zero (0), as the result of which the clutch K3 becomes load-free and can be disengaged. This disengagement of the clutch K3 takes place between the points in time t.sub.2 and t.sub.3.

[0140] In this interval, i.e., between the points in time t.sub.2 and t.sub.3, only the electric motor EM2 drives the motor vehicle 1, since the torques of the internal combustion engine 2 and the electric motor EM1 cancel each other out as described. Starting at the point in time t.sub.3, the torque of the internal combustion engine is reduced further, in order to bring the rotational speed of the transmission input shaft 7 to the rotational speed, at which a ratio with respect to the rotational speed of the countershaft 22 is reached, at which the gearshift clutch C can be engaged.

[0141] Between the points in time t.sub.2 and t.sub.6, in which only or mainly the electric motor EM2 drives, the output torque 53 is lower than in the case of an assistance or take-over by the internal combustion engine 2.

[0142] Starting at the point in time t.sub.5, the generator operation of the electric motor EM1 begins to end. The electric motor EM1 is ramped up to the initial value and/or the initial torque 46. Simultaneously, the torque of the internal combustion engine 2 is also increased to the initial value 44. As soon as the electric motor EM1 has ended the operation as a generator at the point in time t.sub.6, the torque output of the electric motor EM2 is reduced and, in fact, also back to the initial value. At the point in time t.sub.7, the torque output of the electric motors EM1 and EM2 is at the initial value again. The torque output of the internal combustion engine 2 is increased slightly up to the point in time t.sub.8.

[0143] FIG. 9 shows the gear change of a hybrid gear starting from the internal-combustion-engine gear V3 and the electric gear E2 into the electric gear E4. At the point in time t.sub.9, the shift elements are located as the shift elements are at the point in time t.sub.8, i.e., only the rotational speeds 41 and 42 may have changed. At the point in time t.sub.10, the gearshift clutch B is disengaged. The disengagement has ended by the point in time t.sub.11. Starting at this point, the motor torque of the electric motor EM2 is guided to a negative value, in order to adapt, by operation as a generator, the rotational speed of the transmission input shaft 9 to the rotational speed of the transmission input shaft 7 in such a way that the idler gear 24 has the same rotational speed as the shift element 52. The rotational speeds of the transmission input shaft 7 and of the transmission input shaft 9 are therefore not to become identical, but rather are to be adapted in such a way that the rotational speeds of the idler gear 24 and of the engagement device S2 are identical or are identical except for a predefined difference. Thereupon, starting at the point in time t.sub.12, the gearshift clutch D can be engaged, as the result of which the electric motor EM2 outputs torque to the drive output via the gear-step gears of the fourth gear G4. At the point in time t.sub.13, the gearshift clutch D is engaged. Starting at this point in time, the internal combustion engine 2 transmits torque via the gear-step gears of the third gear G3 and the electric motor EM2 transmits torque via the gear-step gears of the fourth gear. The curve 53 of the output torque shows only a slight downturn, since the gear change of the electric motor EM2 is assisted by the internal combustion engine 2 in the time period between the points in time t.sub.11 and t.sub.12, in which no torque from the electric motor EM2 reaches the drive output.

[0144] FIG. 10 shows a configuration as an alternative to FIG. 2, wherein most features and functions are similar to those described with respect to FIGS. 2 through 9. Identical reference numbers label identical components. The first transmission input shaft, which is designed as a solid shaft, also has, for example, the reference character 7. The second transmission input shaft, which is designed as a hollow shaft, has the reference character 9.

[0145] In contrast to FIG. 2, however, the clutch K2 and the gear-step gears 18 and 32 of the fifth gear step G5 are omitted. In place of the clutch K2 and the gear-step gears 18 and 32 of the fifth gear step G5, the gear-step gears 62 and 64 of a purely electrically utilized gear step GE2 have been added. While the gears labeled with a “G” can be electric, internal-combustion-engine, and hybrid gear steps, this is limited to an electric gear step with the gear GE2.

[0146] The crawler gear E1 can be implemented via the gear step G1, wherein, in the example embodiment according to FIG. 10, the second transmission input shaft 9 and the second electric motor EM2 are utilized as a drive.

[0147] The electric motors EM1 and EM2 are power shiftable with each other in this configuration as well.

[0148] In contrast to FIGS. 2 through 4, however, only four internal-combustion-engine forward gears V1, V2, V3, and V4 can be implemented, as shown in FIG. 11. The internal-combustion-engine forward gears V1, V2, V3, and V4 and the electric forward gear E1 are formed via the corresponding mechanical gear stages G1, G2, G3, and G4, i.e., E1 and V1 with G1, V2 with G2, etc. The electric gear E2 has separate gear-step gearwheels 62 and 64, however, and does not utilize the gear-step gearwheels 12 and 26 of the gear step G2, which, at this point, deviates from the nomenclature utilized otherwise in the present application.

[0149] FIG. 11 shows a corresponding shift pattern, which is associated with FIGS. 10 and 12. The particular engaged shift elements are marked by “X”.

[0150] The shift element F is the shift element of the gear step GE2, which is utilized only with the electric motor EM2.

[0151] FIG. 12 shows the hybrid transmission device 3 according to FIG. 10, wherein the hybrid transmission device 3 was designed as a mirror image with respect to the central axis, which extends through the gearwheels 14 and 34 of the gear step G3. From a purely functional perspective, the hybrid transmission devices 3 according to FIGS. 10 and 12 do not differ.

[0152] Modifications and variations can be made to the embodiments illustrated or described herein without departing from the scope and spirit of the invention as set forth in the appended claims. In the claims, reference characters corresponding to elements recited in the detailed description and the drawings may be recited. Such reference characters are enclosed within parentheses and are provided as an aid for reference to example embodiments described in the detailed description and the drawings. Such reference characters are provided for convenience only and have no effect on the scope of the claims. In particular, such reference characters are not intended to limit the claims to the particular example embodiments described in the detailed description and the drawings.

REFERENCE CHARACTERS

[0153] 1 motor vehicle [0154] 2 internal combustion engine [0155] 3 hybrid transmission device [0156] 4 gear set [0157] 5 crankshaft [0158] 6 output part [0159] 7 first transmission input shaft [0160] 8 output part [0161] 9 second transmission input shaft [0162] 10 fixed gear [0163] 11 end [0164] 12 fixed gear [0165] 13 end [0166] 14 idler gear [0167] 15 control device [0168] 16 fixed gear [0169] 18 fixed gear [0170] 20 differential [0171] 22 countershaft [0172] 24 idler gear [0173] 26 idler gear [0174] 30 idler gear [0175] 31 output shaft [0176] 32 idler gear [0177] 33 output shaft [0178] 34 fixed gear [0179] 35 end facing away from the motor [0180] 36 sub-transmission [0181] 37 end facing the motor [0182] 38 sub-transmission [0183] 40 curve [0184] 41 motor speed [0185] 42 motor speed [0186] 43 curve [0187] 44 initial value [0188] 45 initial value [0189] 48 target value [0190] 50 target value [0191] 52 target value [0192] 53 output torque [0193] 54 curve [0194] 60 perpendicular [0195] K1 clutch [0196] K2 clutch [0197] K3 clutch [0198] S1 engagement device [0199] S2 engagement device [0200] S3 engagement device [0201] S4 engagement device [0202] A gearshift clutch [0203] B gearshift clutch [0204] C gearshift clutch [0205] D gearshift clutch [0206] E gearshift clutch [0207] EM1 electric motor [0208] EM2 electric motor [0209] A1 axis [0210] A2 axis [0211] A3 axis [0212] A4 axis [0213] A5 axis