Hybrid module and a drive arrangement for a motor vehicle

Abstract

A hybrid module for a motor vehicle drive train includes an electric machine, a rotor bearing carrier, a first bearing, a second bearing, and an intermediate shaft. The electric machine has a rotor unit with a rotor. The roller bearing carrier is for rotatably supporting the rotor unit. The intermediate shaft is for transmitting a torque between an internal combustion engine and a transmission or an output. The internal combustion engine and, the transmission or the output, can be connected to the hybrid module. The intermediate shaft is rotatably supported by the first bearing and the second bearing. The first bearing or the second bearing is supported on the rotor bearing carrier, supported or on the rotor unit, or is arranged to be supported on an output shaft of the internal combustion engine.

Claims

1. A hybrid module for a motor vehicle drive train comprising: an electric machine comprising a rotor unit with a rotor; a rotationally-fixed rotor bearing carrier for rotatably supporting the rotor unit; a first bearing; a second bearing; a third bearing arranged axially between the first bearing and the second bearing; and, an intermediate shaft for transmitting a torque between an internal combustion engine and a transmission or an output, wherein: the internal combustion engine and, the transmission or the output, can be connected to the hybrid module; the intermediate shaft is rotatably supported by the first bearing and the second bearing; the first bearing is supported on the rotor bearing carrier; the second bearing is supported on the rotor unit; and the third bearing supports the rotor unit on the rotor bearing carrier.

2. The hybrid module of claim 1, a one of the first bearing or the second bearing is a fixed bearing; and, the other of the first bearing or the second bearing is a floating bearing.

3. The hybrid module of claim 2, wherein: the first bearing is a floating bearing; and, the second bearing is a fixed bearing.

4. The hybrid module of claim 3, wherein: the rotor unit comprises a separating clutch for: transmitting a torque from the internal combustion engine to the electric machine; and, separating the electric machine from the internal combustion engine; the separating clutch comprises a counterplate, a pressure plate, and a friction disk; the counterplate is for applying a counterforce to a contact pressure force applied by the pressure plate to transmit a friction torque to the friction disk; and, the second bearing is supported on the counterplate.

5. The hybrid module of claim 4, wherein: the counterplate has an opening with a first maximum radius; the intermediate shaft has a second radius; and, the first maximum radius is greater than the second radius thus allowing the intermediate shaft to be passed through the opening during assembly.

6. A hybrid module for a vehicle comprising: a housing; an electric machine comprising a stator fixed to the housing, and a rotor; a rotor bearing carrier fixed to the housing; an intermediate shaft for coupling to an output shaft of an internal combustion engine; a separating clutch for selectively coupling the intermediate shaft with the rotor; a first bearing in direct contact with the rotor bearing carrier and the intermediate shaft; and, a second bearing in direct contact with the rotor bearing carrier and the intermediate shaft.

7. The hybrid module of claim 6 further comprising a dual mass flywheel drivingly connected to the intermediate shaft and couplable to the output shaft.

8. The hybrid module of claim 6 wherein: the intermediate shaft comprises a connection side proximate the internal combustion engine; the first bearing is a fixed, deep groove ball bearing on the connection side; and, the second bearing is a floating, needle bearing.

9. The hybrid module of claim 6 wherein the first bearing and the second bearing are installed between the intermediate shaft and the rotor bearing carrier.

10. The hybrid module of claim 6 further comprising a second bearing, wherein: the rotor comprises a radially inward leading component part; and, the second bearing contacts the radially inward leading component part and the intermediate shaft.

11. The hybrid module of claim 10 further comprising a third bearing installed on the intermediate shaft for positioning the intermediate shaft in the output shaft.

12. The hybrid module of claim 6 further comprising a second bearing, wherein: the separating clutch comprises a counterplate mechanically connected to the rotor; and, the second bearing contacts the counterplate and the intermediate shaft.

13. The hybrid module of claim 12 wherein: the intermediate shaft comprises a spline with a first outer diameter; the separating clutch comprises a friction disk connected to the intermediate shaft at the spline; and, the second bearing comprises a second outer diameter, greater than the first outer diameter.

14. The hybrid module of claim 6 further comprising a dual-clutch device connected to the rotor by accessible connection points.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The disclosure is explained in detail below against the relevant technical background with reference to the associated drawings, which show example embodiments. The disclosure is not restricted in any way by the purely schematic drawings, and it should be noted that the illustrative embodiments shown in the drawings are not restricted to the dimensions illustrated. In the drawings:

(2) FIG. 1 shows a hybrid module according to a first embodiment,

(3) FIG. 2 shows a hybrid module according to a second embodiment,

(4) FIG. 3 shows a hybrid module according to a third embodiment,

(5) FIG. 4 shows a hybrid module according to a fourth embodiment, and,

(6) FIG. 5 shows a hybrid module according to a fifth embodiment.

DETAILED DESCRIPTION

(7) FIG. 1 shows a hybrid module with a bearing variant for the intermediate shaft 50. The hybrid module 1 comprises an electric machine 20 having a stator 21 and a rotor 31, which is arranged radially on the inside relative to said stator. The rotor 31 is a component part of a rotor unit 30, on which the windings and/or the magnets of the rotor 31 are mounted and which has a radially inward-leading component part 32. The electric machine 20 is accommodated in a housing 14 of the hybrid module 1. In the vicinity of the position of the internal combustion engine 10 there is a set of splines 51, by means of which the intermediate shaft 50 is connected via a drive to the dual-mass flywheel 12, which is in turn coupled to an output shaft 11 of the internal combustion engine.

(8) The rotary motion of the dual-mass flywheel 12 is transmitted to the rotor unit 30 via a separating clutch 70. For this purpose, the separating clutch 70 has a pressure plate 71 and a counterplate 72, which is connected for conjoint rotation to the rotor unit 30.

(9) The rotation of the rotor unit 30 is transmitted to the dual-clutch device 80 and, from there, to an output 3 on the transmission side. For this purpose, the dual-clutch device 80 has a first component clutch 81 and a second component clutch 82.

(10) In the embodiment illustrated in FIG. 1, the intermediate shaft 50 has its smallest shaft diameter in the region facing the internal combustion engine. The subassembly arranged radially to the outside of the intermediate shaft 50, said subassembly comprising the rotor bearing carrier 40 and at least one clutch actuation system 83, has its largest inside diameter on its side facing the internal combustion engine. This radial diameter difference, arising on the side of the intermediate shaft 50 facing the internal combustion engine, of the intermediate shaft 50 and of the radial installation space 93 arising therefrom is used for the arrangement of a fixed bearing 63 embodied as a deep groove ball bearing 90.

(11) The position of the side of the intermediate shaft 50 facing the transmission 13 is used for the arrangement of a needle bearing 94 since the radial installation space 93 between the intermediate shaft 50 and the components adjacent thereto is small there.

(12) The two bearings 60, 61 may be arranged close to the two opposite ends of the intermediate shaft 50. To ensure that the fixed bearing 63 can support axial forces in both directions, both the bearing inner ring 91 and the bearing outer ring 92 rest in both directions against a shoulder or on a fastening element, e.g., in the form of the shaft retaining ring 95 illustrated. In the illustrative embodiment shown in FIG. 1, shaft retaining rings 95 are arranged on both sides of the bearing inner ring 91 of the fixed bearing 63. This allows axial fixing with a minimum radial installation space requirement. As an alternative, however, support for the fixed bearing 63, embodied as a deep groove ball bearing 90, on one side by a shaft shoulder is possible, wherein, in this variant embodiment, the needle bearing diameter should be increased in order to allow assembly.

(13) FIG. 2 shows an embodiment of the hybrid module 1 in which a smaller spacing is implemented between the bearings than is illustrated in FIG. 1. This is implemented by a bearing subassembly 62 which is arranged between the intermediate shaft 50 and the rotor bearing carrier 40. The positions of the bearings illustrated can also be interchanged as a departure from the illustration in FIGS. 1 and 2.

(14) FIG. 3 shows another bearing concept for the intermediate shaft 50. Here, the bearing which performs the function of a floating bearing 64 is a needle bearing 94 and is arranged on the side of the intermediate shaft 50 facing the internal combustion engine. The fixed bearing 63, which is embodied as a deep groove ball bearing 90, is arranged on the side of the intermediate shaft 50 which faces the transmission. As in the illustrative embodiment shown in FIG. 1, the floating bearing 64 is arranged between the intermediate shaft 50 and the rotationally fixed rotor bearing carrier 40.

(15) Here, however, the fixed bearing 63 is arranged between the intermediate shaft 50 and the rotor 31 of the electric machine 20. Although the fixed bearing 63 has a larger diameter than the illustrative embodiment shown in FIG. 1, this is not disadvantageous since, in the closed state of the separating clutch 70, the intermediate shaft 50 and the rotor 31 of the electric machine 20 rotate at the same speed, and therefore, as a consequence, there is no relative speed and thus also there are no bearing losses in the fixed bearing 63. When considering the entire driving cycle, this compensates for the potentially high losses due to the larger bearing diameter.

(16) In order to keep the diameter small in this arrangement too, the seat of the fixed bearing 63 on the rotor 31 is shifted radially inward to such an extent that the installation of the rotor main bearing 100 is only just possible.

(17) Installation is performed as follows: first of all, the rotor bearing carrier 40 and the rotor 31 are connected to one another by the rotor main bearing 100, here consisting of two angular ball bearings. In this bearing assembly, which should run in a particularly rigid and play-free manner, the bearing play can be adjusted by means of a shaft nut. The installation of the shaft nut is possible since the bearing seat on the rotor 31, which is provided for the as yet uninstalled fixed bearing 63 of the intermediate shaft 50, is so large that the shaft nut can be passed through it and then screwed onto the rotor bearing carrier 40.

(18) After the bearing of the intermediate shaft 50 serving as a floating bearing 64 has been preinstalled on the rotor bearing carrier 40 and the fixed bearing 63 has been preinstalled on the intermediate shaft 50, the intermediate shaft 50 can be inserted into the rotor bearing carrier 40 and fixed axially by securing the fixed bearing 63 on the seat of the rotor 31. In this illustrative embodiment, the seat of the rotor is situated on the radially inward-leading component part 32 of the rotor unit 30.

(19) A separating clutch connecting element 76 of the dividable separating clutch 70 is then mounted on the set of splines 51 of the intermediate shaft 50 and connected to the separating clutch friction disk 74. When the intermediate shaft 50, the separating clutch 70 and the rotor 31 of the electric machine 20 have been assembled to form a structural unit, the main clutch of the hybrid module 1, which can be a dual-clutch device 80 for example, can then be connected to the rotor 31. For this purpose, the illustrative embodiments shown in FIGS. 2 to 5 have easily accessible connection points between the rotor 31 and the clutch.

(20) FIG. 4 shows a variant of the illustrative embodiment shown in FIG. 3. Here, however, the bearing serving as a floating bearing 64 is not arranged between the intermediate shaft 50 and the rotor bearing carrier 40, but between the intermediate shaft 50 and the output shaft 11 of the internal combustion engine, which is preferably a crankshaft. This reduces the bearing losses since, apart from the movements of the torsional vibration damper, no relative speed arises between the output shaft 11 of the internal combustion engine and the intermediate shaft 50.

(21) FIG. 5 shows another variant of the hybrid module 1, which is similar to the illustrative embodiment from FIG. 3. In this illustrative embodiment too, the fixed bearing 63 of the intermediate shaft 50 is situated between the intermediate shaft 50 and the rotor 31. Here, however, the fixed bearing 63 is not connected directly to the radially inward-leading component part 32 of the rotor unit 30 but is connected indirectly in a mechanical way to the rotor 31 by means of the counterplate 72 of the separating clutch 70, which is a component part of the rotor unit 30. In this arrangement, assembly is possible even without a dividable separating clutch disk. The fixed bearing 63 is situated on that side of the set of splines connecting the intermediate shaft 50 to the separating clutch disk which faces the transmission. As a result, the separating clutch friction disk 74 does not cover the axial fastening elements of the fixed bearing 63.

(22) In order to minimize the bearing losses of the fixed bearing 63, the bearing race of the fixed bearing 63 lies on a relatively small diameter, despite the large outer fastening diameter between the counterplate 72 and the fixed bearing 63. The large outer fastening diameter of the fixed bearing subassembly offers the advantage that the counterplate 72 has, radially on the inside, an opening 73 of sufficient size to enable the intermediate shaft 50 to be inserted through this opening 73. This makes it possible to fully assemble the subassembly comprising the rotor 31 of the electric motor, the rotor bearing carrier 40, the separating clutch 70 and the separating clutch actuation system 75 and to test the functioning of the clutch before the intermediate shaft 50 is installed.

(23) Alternatively, the inside diameter of the opening 73 of the counterplate 72 is smaller than the outside diameter of the intermediate shaft 50, thereby making it possible to fasten the counterplate 72 on the rotor 31 only after the insertion of the intermediate shaft 50. In the illustrative embodiment shown in FIG. 5, the large outside fastening diameter of the fixed bearing subassembly is made possible by a bearing outer ring 92 of the fixed bearing which is very thick in the radial direction. Alternatively, a further component part can also be inserted between the fixed bearing 63 and the counterplate 72 in order to bridge the radial spacing and connect the two component parts to one another.

(24) The possibility of shifting the bearing race radially inward by means of a thick bearing outer ring 92 or an intermediate component, despite a significantly larger outer bearing fastening diameter predetermined by the assembly concept, can also be used in the illustrative embodiments shown in FIGS. 3 and 4 to reduce the bearing losses.

(25) Likewise as an addition or as an alternative, adjacent component parts can be supported or mounted on the intermediate shaft 50. In the embodiments illustrated in the figures, this is illustrated by way of example for a transmission input shaft, which is supported on the intermediate shaft 50 by means of a floating bearing 64 embodied as a needle bearing 94.

(26) The embodiments of the fixed bearing 63 and the floating bearing 64 which are presented in the various illustrative embodiments and the connections of said bearings can also be combined with one another in any desired manner.

(27) The hybrid module according to the disclosure is embodied with different bearing arrangements for the intermediate shaft which are distinguished by compact construction and low bearing losses produced by drag torques since the embodiment according to the invention of the hybrid module makes it possible to embody the bearings with very small radial dimensions and, consequently, to arrange them with a minimum radial spacing with respect to the axis of rotation of the intermediate shaft.

REFERENCE LABELS

(28) 1 hybrid module 2 input 3 output 4 axis of rotation 10 position of the internal combustion engine 11 output shaft of the internal combustion engine 12 dual-mass flywheel 13 position of the transmission 14 housing 20 electric machine 21 stator 30 rotor unit 31 rotor 32 radially inward-leading component part 40 rotor bearing carrier 50 intermediate shaft 51 set of splines 60 first bearing 61 second bearing 62 bearing subassembly 63 fixed bearing 64 floating bearing 70 separating clutch 71 pressure plate 72 counterplate 73 opening 74 separating clutch friction disk 75 separating clutch actuation system 76 separating clutch connecting element 80 dual-clutch device 81 first component clutch 82 second component clutch 83 clutch actuation system 90 deep groove ball bearing 91 bearing inner ring 92 bearing outer ring 93 radial installation space 94 needle bearing 95 shaft retaining ring 100 rotor main bearing