DE102020130416B4 - Separating clutch for a hybrid powertrain in P1 and P3 architecture - Google Patents

Abstract

Clutch unit (1) for coupling a motor shaft of an internal combustion engine with a second output shaft (3), which can be connected to a rotor of an electric machine, with a dual-mass flywheel (5) for damping torsional vibrations, the dual-mass flywheel (5) being connected directly to the motor shaft or indirectly connectable primary mass (6) and a secondary mass (7) which can be rotated to a limited extent via an energy storage element (8) designed in particular as an arc spring (9), the secondary mass (7) having an output flange (10) which can be tangentially attached to the energy storage element (8). and a friction clutch (11) for coupling the secondary mass (7) to the second output shaft (3), the output flange (10) having a friction surface (14) for frictional contact with an axially displaceable clutch disk (1) which can be coupled to the second output shaft (3). 15) of the friction clutch (11), the output flange (10) having a clutch cover (20) for axially supporting an actuating element (21) for displacing a pressure plate (23) for axially pressing the clutch disc (15) between the pressure plate (23) and is connected to the output flange (10), the output flange (10) having a first output hub (12) for connection to a first output shaft (2) which can be connected to a rotor of an electric machine, the output flange (10) being axially opposed to the primary mass ( 6) is supported.

Description

The present invention relates to a clutch unit with a friction clutch as a separating clutch with two output shafts for connection to an electric machine and a transmission.

Hybrid powertrains for motor vehicles are known in various architectures with regard to the arrangement of the one or more electric machines in relation to the internal combustion engine. A possible architecture is the P1 and P3 (P1 + P3) architecture, in which a first electric machine is constantly connected to the motor shaft of the internal combustion engine and a second electric machine is arranged behind the transmission, which is connected to the motor shaft via a separating clutch can be separated. Behind the transmission means that the separating clutch couples the transmission input shaft from the motor shaft and the second electric machine is connected to the transmission output shaft. Clutch units with two output shafts in which the actuating force is supported axially on the transmission input shaft are assumed to be known. In certain configurations, this leads to disadvantages with regard to the assembly of the clutch unit. Furthermore, these clutch units are quite large, particularly in the axial direction, so that it is difficult to accommodate an additional centrifugal pendulum.

In the two older ones, but not previously published DE 10 2020 121 200 A1 and DE 10 2020 119 278 A1 clutch units are disclosed for coupling a motor shaft of an internal combustion engine with a second output shaft, which can be connected to a rotor of an electric machine, with a dual-mass flywheel for damping torsional vibrations, the dual-mass flywheel having a primary mass that can be connected directly or indirectly to the motor shaft and a primary mass via a, in particular designed as an arc spring, energy storage element which can be rotated to a limited extent, the secondary mass having an output flange which can be tangentially abutted on the energy storage element, and a friction clutch for coupling the secondary mass to the second output shaft, the output flange having a friction surface for frictional contact with one which can be coupled to the second output shaft axially displaceable clutch disc of the friction clutch, the output flange being connected to a clutch cover for axially supporting an actuating element for displacing a pressure plate for axially pressing the clutch disc between the pressure plate and the output flange, and wherein the output flange is axially supported against the primary mass.

Proceeding from this, the present invention is based on the object of at least partially overcoming the problems known from the prior art.

This problem is solved with the features of independent claim 1. Further advantageous embodiments of the invention are specified in the dependent claims. The features listed individually in the dependent claims can be combined with one another in a technologically sensible manner and can define further embodiments of the invention. In addition, the features specified in the claims are specified and explained in more detail in the description, with further preferred embodiments of the invention being presented.

The clutch unit according to the invention for coupling a motor shaft of an internal combustion engine with a second output shaft, in particular a transmission input shaft, which can be connected to a rotor of an electric machine, comprises a dual-mass flywheel for damping torsional vibrations, wherein the dual-mass flywheel has a primary mass that can be connected directly or indirectly to the motor shaft and a has a secondary mass that can be rotated to a limited extent via an energy storage element, in particular designed as one or more arc springs, the secondary mass having an output flange which can be tangentially attached to the energy storage element. Furthermore, the clutch unit comprises a friction clutch as a separating clutch for coupling the secondary mass with the second output shaft, the output flange having a friction surface for frictional contact with an axially displaceable clutch disk of the friction clutch that can be coupled to the second output shaft, the output flange having a clutch cover for axially supporting an actuating element for displacing a pressure plate for axially pressing the clutch disc between the pressure plate and the output flange, the output flange having a first output hub for connection to a first output shaft that can be connected to a rotor of an electric machine, the output flange being axially supported against the primary mass.

In the context of this document, the term axial is understood to refer to the extension of the axes of rotation of the output shafts. The configuration proposed here allows the axially compact design of a clutch unit for a P1 + P3 architecture of a hybrid drive train of a motor vehicle, in which the actuating forces of the friction clutch in the axial direction on the primary mass and thus on the engine shaft of the internal combustion force machine must be supported. At the same time, the compact design makes it possible to optionally accommodate a centrifugal pendulum in the clutch unit. This enables free design of clutch units for hybrid drive trains in P1+P3 architecture with good mountability.

The primary mass preferably has a cover disk in the area of the support and the output flange is supported on the cover disk. The cover disk is understood to mean a component which is formed on the inner diameter of the primary mass and thus preferably has a substantially circular geometry in a plane transverse to the axial direction and at the same time preferably has a collar in the axial direction. The design of the cover plate ensures good centerability during assembly.

The output flange is preferably supported against the primary mass via a bearing, which in particular comprises one of the following components: a friction ring, a plain bearing or a ball bearing, which depends on the application, in particular depending on the available installation space, on the torques to be transmitted and/or the installation space available for assembly can be selected. The realization of the storage via a friction ring can be done cost-effectively with a simple structure of the adjacent components and simple assembly. A plain bearing advantageously offers good radial and axial running properties and requires little installation space in the radial direction. The storage via a ball bearing ensures good running properties with good support of the applied force.

The clutch unit preferably further comprises a centrifugal pendulum, which is connected, in particular in a rotationally fixed manner, to the output flange. The centrifugal pendulum comprises a centrifugal pendulum flange and at least one pendulum mass, which can move on predetermined trajectories depending on the applied rotation frequency. By defining the movement path, the centrifugal pendulum flange and the pendulum masses, attenuation or even cancellation of individual frequencies can be achieved in order to be able to cancel or significantly reduce particularly disturbing frequencies.

As a precaution, it should be noted that the number words used here (“first”, “second”,...) primarily serve (only) to distinguish between several similar objects, sizes or processes, i.e. in particular no dependency and/or order of these objects, sizes or prescribe processes to each other. If a dependency and/or sequence is required, this is explicitly stated here or it will be obvious to the person skilled in the art when studying the specifically described embodiment.

• 1: eine schematische Schnittansicht eines ersten Beispiels eines Kupplungsaggregats;
• 2: eine schematische Schnittansicht eines zweiten Beispiels eines Kupplungsaggregats;
• 3: eine schematische Schnittansicht eines dritten Beispiels eines Kupplungsaggregats;
• 4: eine schematische Schnittansicht eines vierten Beispiels eines Kupplungsaggregats;
• 5: eine schematische Schnittansicht eines fünften Beispiels eines Kupplungsaggregats; und
• 6: eine schematische Schnittansicht eines sechsten Beispiels eines Kupplungsaggregats.

The invention and the technical environment are explained in more detail below using the figures. It should be noted that the invention is not intended to be limited by the exemplary embodiments shown. In particular, unless explicitly stated otherwise, it is also possible to extract partial aspects of the facts explained in the figures and to combine them with other components and findings from the present description and/or figures. In particular, it should be noted that the figures and in particular the proportions shown are only schematic. The same reference numbers designate the same objects, so that explanations from other figures can be used in addition if necessary. Show it:

• 1 : a schematic sectional view of a first example of a clutch unit;
• 2 : a schematic sectional view of a second example of a clutch assembly;
• 3 : a schematic sectional view of a third example of a clutch assembly;
• 4 : a schematic sectional view of a fourth example of a clutch assembly;
• 5 : a schematic sectional view of a fifth example of a clutch assembly; and
• 6 : a schematic sectional view of a sixth example of a clutch assembly.

1 shows a first example of a clutch unit 1 for coupling a motor shaft, not shown, of an internal combustion engine with a second output shaft 3. The clutch unit 1 can also be connected to a first output shaft 2. First output shaft 2 and second output shaft 3 can each be connected to a rotor of an electric machine. A gear is usually formed between the second output shaft 3 and the corresponding electric machine, which enables the selection of the gear ratio. The clutch unit 1 is used in particular for coupling and uncoupling the internal combustion engine in a hybrid drive train of a motor vehicle, which consists of the internal combustion engine on the one hand and two electrical machines connected to the first output shaft 2 and the second output shaft 3. The connection to the engine shaft takes place via a crankshaft screw connection 4. The clutch unit 1 has a dual-mass flywheel 5, which is designed to dampen torsional vibrations. For this purpose, the dual mass flywheel 5 also has a primary mass 6 Called a flywheel, which can be connected to the engine shaft via the crankshaft screw connection 4. Furthermore, the dual-mass flywheel 5 includes a secondary mass 7, which can be rotated to a limited extent against the primary mass 6 via an energy storage element 8, which comprises a plurality of arc springs 9. The secondary mass 7 has an output flange 10 which can be attached tangentially to the energy storage element 8. Furthermore, the clutch unit 1 includes a friction clutch 11 for coupling the secondary mass 7 to the second output shaft 3. The connecting flange 10 has a first output hub 12, which can be connected to the first output shaft 3, in particular via a first toothing 13. Instead of a first toothing 13, the first output hub 12 can also be caulked to the first output shaft 2. The motor shaft and the first output shaft 3 are therefore constantly connected via the dual-mass flywheel 5. The corresponding electrical machine (not shown) connected to the first output shaft 2 is therefore designed in a so-called P1 configuration.

Furthermore, the output flange 10 comprises a friction surface 14 for frictional contact with an axially displaceable clutch disc 15 of the friction clutch 11 which can be coupled to the second output shaft 3. The term axial here refers to the axis of rotation of the output shafts 2, 3. The clutch disc 15 has a friction lining 16 and a spring segment 17. The clutch disk 15 is connected to the second output shaft 3 via a second output hub 18 with a second toothing 19. The output flange 10 also has a clutch cover 20 for axially supporting an actuating element 21, here a lever spring 22, for displacing a pressure plate 23 for axially pressing the clutch disc 15 between the pressure plate 23 and the output flange 10. The output flange 10 is axially supported against the primary mass 6. For this purpose, the primary mass 6 has a cover disk 24, which at the same time enables the clutch unit 1 to be centered. An axial bearing 35, which in this example is realized via a friction ring 25 on the cover disk 24, provides axial support for the actuating forces, i.e. from the actuating element 21 via the clutch cover 20 to the output flange 10 and from this via the friction ring 25 to the cover disk 24 and thus via the primary mass 6 to the motor shaft. This enables easy assembly of the clutch unit 1 and at the same time enables a compact structure of the same.

Furthermore, the compact design also allows the space-saving design of a centrifugal pendulum 26, which serves to further dampen certain vibration modes. The centrifugal pendulum 26 here has a centrifugal pendulum flange 27, which is connected to the output flange 10 in a rotationally fixed manner. The centrifugal pendulum 26 also has pendulum masses 28, which are connected to one another via rivets 30 and rollers (not shown here) through openings in the centrifugal pendulum flange 27 and which can be moved in certain movement paths 29 predetermined by openings 31 in the centrifugal pendulum flange 27 and thus dampen or can pay off.

2 shows a schematic sectional view of a second example of a clutch unit 1. Only the differences from the first example of a clutch unit 1 should be described here, otherwise reference is made to the above statements. In the second example, the clutch unit 1 lacks the centrifugal pendulum 26, so that the clutch unit 1 is even more compact in the axial direction.

3 shows a schematic sectional view of a third example of a clutch unit 1. Only the differences from the previous examples of a clutch unit 1 should be described here, otherwise reference is made to the above statements, in particular to the statements on the first example, since the third example also has a centrifugal pendulum 26 includes. In the third example, in contrast to the first example, the clutch unit 1 has a plain bearing 32 as a bearing 35 instead of a friction ring 25. If necessary, a sliding ring 33 can be formed axially between the sliding bearing 32 and the primary mass 6 or cover disk 24.

4 shows a schematic sectional view of a fourth example of a clutch unit 1. Only the differences from the previous examples of a clutch unit 1 should be described here, otherwise reference is made to the above statements. The fourth example of a clutch unit 1 is similar to the third example with the difference that the fourth example does not have a centrifugal pendulum.

5 shows a schematic sectional view of a fifth example of a clutch unit 1. Only the differences from the previous examples of a clutch unit 1 should be described here, otherwise reference is made to the above statements, in particular to the statements on the first and third examples, since the fifth example is also one Centrifugal pendulum 26 includes. In this example, the bearing 35 is realized in the axial direction by a ball bearing 34, via which the first output flange 12 is supported in the axial direction on the cover plate 24 and thus on the primary mass 6 of the dual-mass flywheel 5.

6 shows a schematic sectional view of a sixth example of a clutch unit 1. Only the differences from the previous examples of a clutch unit 1 should be described here, otherwise reference is made to the above statements. The sixth example of a clutch unit 1 is similar to the fifth example with the difference that the fourth example does not have a centrifugal pendulum.

The clutch unit 1 proposed here allows the compact design of a separating clutch for hybrid drives that are designed in P1 and P3 architecture, in which the motor shaft of the internal combustion engine is always connected to a first electrical machine via a first output shaft 2 and via a friction clutch 15 a second drive shaft 3, the transmission input shaft, can be coupled. The electric machine in P3 architecture is usually arranged behind the transmission in the direction of power flow. The compact design allows the formation of a centrifugal pendulum 26 in addition to the dual-mass flywheel 5 while at the same time supporting the actuating force in the axial direction on the motor shaft.

Reference symbol list

1

Clutch unit

2

First output shaft

3

Second output shaft

4

Crankshaft screw connection

5

Dual mass flywheel

6

Primary mass

7

secondary mass

8th

Energy storage element

9

bow spring

10

Connection flange

11

Friction clutch

12

First output hub

13

First gearing

14

friction surface

15

Clutch letter

16

friction lining

17

Spring segment

18

Second output hub

19

Second gearing

20

Clutch cover

21

Actuator

22

Lever spring

23

pressure plate

24

cover plate

25

Friction ring

26

centrifugal pendulum

27

Centrifugal pendulum flange

28

pendulum mass

29

trajectory

30

rivet

31

opening

32

bearings

33

Sliding ring

34

ball-bearing

35

storage

Claims (5)

Clutch unit (1) for coupling a motor shaft of an internal combustion engine with a second output shaft (3), which can be connected to a rotor of an electric machine a dual-mass flywheel (5) for damping torsional vibrations, the dual-mass flywheel (5) having a primary mass (6) that can be connected directly or indirectly to the motor shaft and a secondary mass (7) that can be rotated to a limited extent via an energy storage element (8), in particular designed as an arc spring (9). ), wherein the secondary mass (7) has an output flange (10) which can be tangentially attached to the energy storage element (8), and a friction clutch (11) for coupling the secondary mass (7) to the second output shaft (3), wherein the output flange (10) has a friction surface (14) for frictional contact with an axially displaceable clutch disk (15) of the friction clutch (11) which can be coupled to the second output shaft (3), wherein the output flange (10) is connected to a clutch cover (20) for axially supporting an actuating element (21) for displacing a pressure plate (23) for axially pressing the clutch disc (15) between the pressure plate (23) and the output flange (10), wherein the output flange (10) has a first output hub (12) for connection to a first output shaft (2) which can be connected to a rotor of an electric machine, wherein the output flange (10) is axially supported against the primary mass (6). Clutch unit (1). Claim 1 , in which the primary mass (6) is in the area of the support has a cover disk (24) and the output flange (10) is supported on the cover disk (24). Clutch unit (1) according to one of the preceding claims, in which the output flange 10 is supported against the primary mass (6) via a bearing (35). Clutch unit (1). Claim 3 , in which the bearing (35) of the output flange (10) against the primary mass (6) comprises one of the following components: - a friction ring (25); - a plain bearing (32); or - a ball bearing (34). Clutch unit (1) according to one of the preceding claims, further comprising a centrifugal pendulum (26) which is connected to the output flange (10).

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