Multi-plate clutch assembly with sheet metal piston for actuating the clutches, in particular a triple-plate clutch

Description

[0001] The present invention relates to a multi-plate clutch arrangement with at least two friction clutches, which have radially offset plate packs arranged on plate carriers, with pistons which serve to actuate the friction clutches, wherein the pistons delimit pressure chambers from centrifugal oil compensation chambers. State of the art

[0002] Dual clutches for a drivetrain are known, for example, from EP 2 905 492 B1. Such clutch arrangements serve in motor vehicle drivetrains to connect a drive motor, such as an internal combustion engine, to a transmission, such as a stepped transmission. The clutch contained therein serves, for example, for starting and / or interrupting the power flow if a gear change is required in the transmission. With wet friction clutches, it is known to actuate them fluidically. For this purpose, it is also known to provide a rotary feedthrough between a housing journal and a hub member, whereby fluid for cooling and actuating the clutch is supplied via the rotary feedthrough.

[0003] In such an open system, the aim is to counteract the sometimes disruptive effects of centrifugal force on rotating actuating pistons—namely, pressure increases caused by the cooling oil, intended for clutch actuation, being flung outwards by centrifugal force during rotation—by providing corresponding compensation chambers in which a corresponding counter-pressure is generated. As a result, the actuating piston is surrounded on both sides by oil chambers, leading to effective centrifugal oil equalization. These oil chambers consist of pressure oil chambers and centrifugal oil equalization chambers, the latter being formed by centrifugal oil equalization pistons. Centrifugal oil refers to the portion of the cooling oil that is moved by centrifugal force.

[0004] Such dual clutches are also used for hybrid drive systems in a dual-clutch transmission. For example, a design with an electric machine connected to one of the two sub-transmissions is known from DE 10 2010 004 711 B1.

[0005] The connection of the electric motor to one of the sub-transmissions—either the second sub-transmission TG2 with gears 2 / 4 / 6 or the first sub-transmission TG1 with gears 1 / 3 / 5 / 7—does not allow for shifting in purely electric mode without interrupting traction. In a 2.5 hybrid system, shifting in purely electric mode can only occur either with an interruption of traction or via a supporting torque from the combustion engine. This means that the avoidance of emissions cannot be guaranteed, which is detrimental to the test cycle of a hybrid vehicle.

[0006] These problems do not occur in a P2 hybrid type; however, the P2 configuration requires an additional clutch K0 between the combustion engine and the electric motor. Due to limited installation space, a triple-plate clutch is used. All components must be optimized for the limited installation space, and manufacturing and / or assembly costs also play a role.

[0007] A triple coupling is known, for example, from DE 10 2019 104 073 A1.

[0008] DE 10 2018 122 377 A1 discloses a coupling arrangement with at least two friction couplings. At least one of the pistons is made of sheet metal. This piston has an injection-molded seal. Another seal, on the other hand, is injection-molded onto the housing itself. Together, they seal a pressure chamber.

[0009] FR 3 097 917 A1 shows a coupling arrangement with three friction couplings arranged radially offset from each other.

[0010] The object of the invention is to provide a multi-plate clutch arrangement, in particular a triple-plate clutch, in which optimized designs of the pistons with sealing functions are used. Description of the invention

[0011] The problem is solved with a multi-plate clutch arrangement with at least two friction clutches, which have radially offset plate packs arranged on plate carriers, with pistons for actuating the friction clutches, wherein the pistons delimit pressure chambers from centrifugal oil compensation chambers, characterized in that at least one of the pistons is made of sheet metal in one piece.

[0012] According to the invention, the pistons have seals that are vulcanized to the sheets of the pistons and seal at least the respective pressure chamber against other components of the multi-plate clutch.

[0013] The pistons have seals in the form of sealing lips to seal the centrifugal oil compensation chambers.

[0014] The pistons have seals as running surfaces for the respective centrifugal oil compensation pistons.

[0015] The multi-plate clutch assembly has a toothed ring mounted on a toothed ring carrier plate on a main hub, the toothed ring having a space as a pressure chamber in which the piston of the clutch, which represents a disconnecting clutch between an internal combustion engine and a gearbox, is positioned with its radial part and an axial part.

[0016] The multi-plate clutch arrangement is designed as a triple-plate clutch with a first, a second and a third friction clutch, which have radially offset lamellar packs arranged on lamellar carriers, with a first piston, a second piston and a third piston for actuating the first, second and third friction clutch, wherein a first, a second and a third centrifugal oil compensation piston together with the first, the second and third pistons respectively form centrifugal oil compensation chambers, wherein the piston of the middle clutch is a one-piece sheet metal component with three seals.

[0017] Radially offset from each other means that if you follow a jet away from the central axis A, you will successively come across the centrifugal oil compensation chambers, which are also arranged at a radial distance from each other.

[0018] This results in a very compact design with minimal axial expansion. Description of the characters

[0019] Figure 1 shows an embodiment according to the invention with a common drive plate carrier for the clutches K0 and K1, Figure 2 shows an embodiment with a common drive plate carrier for clutches K1 and K2, Figure 3 shows a design with an oil passage in the rotating main hub in the clutch housing, Figure 4 shows the modular structure, Figure 5 shows another embodiment, Figure 6 shows a detail of the pistons.

[0020] All embodiments are concentric triple-plate clutches with an axially short design and a cost-optimized structure through the use of sheet metal components.

[0021] Figure 1 is a triple lamellar coupling 1 with a coupling K2, a coupling K1 and a coupling K0, which are arranged with concentrically arranged lamellar packs from the inside out.

[0022] The lamellar packs of the three couplings K0, K1, K2 have no offset from each other in the axial direction or are only installed with a slight offset from each other.

[0023] The triple-plate clutch 1 has a main hub 2 with oil passages 2a. The oil supply is provided via a rotary union 3 with oil passages 3a, which are sealed by piston rings 3b.

[0024] An input hub 4 engages a first output hub 5 and a second output hub 6. A support disc 7 is attached to the input hub 4 and is connected via a support 8 to a common lamellar carrier 9 for the clutches K0 and K1. This support disc 7 is shown again in Figure 9.

[0025] In this embodiment, the support 8 and the support disc 7 are constructed in multiple parts according to Fig. 9.

[0026] The common lamellar carrier 9 serves as the inner lamellar carrier of coupling K0 and as the outer lamellar carrier of coupling K1. The inner lamellar carrier 10 of coupling K1 is connected to the first output hub 5. Coupling K2 has an outer lamellar carrier 11 and an inner lamellar carrier 12, the inner lamellar carrier 12 being connected to the second output hub 6.

[0027] The three clutches K0, K1, K2 are actuated by means of a first piston 13, a second piston 14, and a third piston 15. The pistons 13, 14, 15 move in their respective pressure chambers 40, 41, 42 against the centrifugal oil compensation chambers 21, 22, 23. All three pistons 13, 14, 15 are arranged on the same side of the triple-plate clutch 1, opposite the input hub 4. The pistons 14, 15 are radially offset from one another and lie within basket sections 9A, 11A of the plate carriers 9, 11, each of which is connected to the main hub 2. Sections 9A and 11A run parallel to each other over a large radial area until they merge into sections 9B and 11B of the plate carriers, which extend at right angles to them.

[0028] A piston carrier 19 for the first piston 13 also runs parallel to the radially extending sections 9A and 11A of the lamellar carriers.

[0029] Furthermore, the triple lamellar clutch 1 also has centrifugal oil compensating pistons, a first centrifugal oil compensating piston 16, a second centrifugal oil compensating piston 17 and a third centrifugal oil compensating piston 18.

[0030] The first piston 13 and the first centrifugal oil compensation piston 16 form a first centrifugal oil compensation chamber 21.

[0031] The second piston 14 and the second centrifugal oil compensation piston 17 form a second centrifugal oil compensation chamber 22.

[0032] The third piston 15 and the third centrifugal oil compensation piston 18 form a third centrifugal oil compensation chamber 23.

[0033] The centrifugal oil compensation chambers 21, 22, 23 are arranged concentrically with a radial distance between them, and all three centrifugal oil compensation chambers 21, 22, 23 are interconnected. The radial offset of the centrifugal oil compensation chambers, which also prevents any radial overlap of the centrifugal oil compensation chambers, enables a compact design in the axial direction.

[0034] The outer centrifugal oil compensation chambers are filled via the third centrifugal oil compensation chamber 23, which fills the second centrifugal oil compensation chamber 22 via an oil passage 24 in the third piston 15 and an oil passage 25 in the outer plate carrier 12 of the clutch K2. The second centrifugal oil compensation chamber 22 fills the first centrifugal oil compensation chamber 21 via a channel 26 between the components of the second piston 14 and an opening 27 in the common plate carrier 9.

[0035] This provides a continuous flow of centrifugal oil from the main hub 2 to the first centrifugal oil equalization chamber 21.

[0036] In the Figure 2 An alternative solution is presented which differs only in that a common lamellar carrier 11 carries the two couplings K1 and K2, while coupling K0 is guided separately with its own inner lamellar carrier 9 and outer lamellar carrier.

[0037] Figure 3 shows an embodiment which essentially differs in the coupling arrangement and cooling oil flow of the Figure 1 corresponds.

[0038] In contrast to the solution of Figure 1 The radial support disc 7 is not made in multiple parts, but in one piece, which reduces costs and is shown again in detail in Figure 7.

[0039] Furthermore, the rotary union 3 for oil passage has been replaced by the rotating main hub 2 in the clutch housing. Eliminating the rotary union 3 as a separate component reduces costs.

[0040] The triple-plate clutch 1 is designed for the configuration of a P2 hybrid drive and enables the electric machine, which engages on the output side of the clutch K0 but before the clutches of the dual-clutch transmission, to shift without interruption of traction with the dual-clutch transmission.

[0041] Figure 5 shows another embodiment in which the sheet metal parts used are further optimized.

[0042] The main hub 2 is designed as a turned part and supports, among other things, the lamellar carriers 9 and 11. A gear ring carrier plate 20 is also directly connected to the main hub 2. The main hub 2 is designed with the smallest possible diameter to allow for small weld diameters for the components to be welded. The diameter of the welds, and thus of the main hub 2, is predetermined for the calculated load.

[0043] The gear ring carrier plate 20 is definitely welded to the main hub 2, while the lamellar carriers 9, 11 may also be connected by a press fit.

[0044] On the outer radius of the gear ring carrier plate 20, which points away from the main hub 2, sits a gear ring 30, which belongs to the connection of the electric machine of the drive train.

[0045] The stamped sheet metal parts of the lamellar carriers 9, 11, and the toothed ring carrier plate 20 may be too flexible to withstand the applied contact pressure. Therefore, an increase in stiffness is desirable. This increase in stiffness is achieved by welding 31 between segments such as the toothed ring carrier plate 20 to the lamellar carrier 9 and the lamellar carrier 9 to the lamellar carrier 11. This stiffening by welding 31 takes place in the area extending radially outwards from the main hub 2, where the segments run parallel to each other.

[0046] Depending on the design of the triple-plate clutch 1, the welds are made either both or alternatively only one of the two welds 31.

[0047] A further improvement results from the design of the main hub 2 as a turned part. The main hub 2 is made of unhardened material, which is easy to machine. This main hub 2 terminates in an edge 32, which is shown as a nose in the sectional view, in the direction of the output hubs 5, 6.

[0048] The edge is manufactured in one piece with the main hub 2 and limits the underlying storage space for the centrifugal oil and serves as a centrifugal oil edge.

[0049] As in the Figure 4The triple-plate clutch 1 is shown in such a way that the outermost clutch K0 can also be omitted, thus enabling the implementation of a P1 hybrid drive. In the P1 configuration, the electric motor is located upstream of the transmission on the crankshaft, therefore functionally largely corresponding to the transmission-side P2 arrangement on the transmission input shaft.

[0050] The installation space remains the same in all embodiments of the invention, as does the overall structure; only the components associated with the coupling K0 are omitted.

[0051] Figure 6 shows details of piston 13 for clutch K0 and piston 14 for clutch K1.

[0052] The piston 13 is a single piece. The piston initially extends radially before transitioning into an axial section at a 90° bend. The axial section includes a step and terminates bluntly in the center of a clutch plate pack K0. The radial section and the first axial section of the piston 13 are located in a space 30C, which is completely enclosed by the gear ring 30 and forms the piston chamber. The gear ring 30 consists of an outwardly facing toothed section, to which the electric motor engages, and an arm 30D, which is attached to the clutch plate carrier 9. The contact point 30A between the arm 30D and the clutch plate carrier 9 is either welded or press-fitted. Furthermore, the gear ring 30 has a passage 30B through which centrifugal oil is guided.

[0053] The piston 13 has a seal 13A, which is vulcanized to the sheet metal component of the piston 13. The seal 13A seals the piston 13 against the installation space 30C.

[0054] The piston 14 for actuating the clutch K 1 is manufactured from a single sheet metal component. The piston again has a radially outwardly extending section which, after a 90° bend, terminates in an axially stepped profile. The piston 14 has a passage 14B for the flow of centrifugal oil. The passage 14B corresponds to an opening 9C in the lamellar carrier 9.

[0055] Seals 14A are also vulcanized onto piston 14, sealing the pressure chamber.

[0056] The piston 14 also has a seal 14C, which seals the centrifugal oil compensation chamber 22 against the lamellar carrier 9. A further seal 14D is also manufactured together with the piston. The seal 14D serves as a running surface for the centrifugal oil compensation piston 17. Reference sign

[0057] 1 Triple-plate clutch 2 Main hub 2a, 3a, 24, 25 Oil passages 3 Rotary feedthrough 3b Piston rings 4 Input hub 5, 6 Output hub 7 Support disc 8 Support 9, 10, 11, 12 Plate carrier 9A, 11A Basket section 9B, 11B Right-angled areas of the plate carrier 9C Opening 13, 14, 15 Actuation piston 14A, 14C, 14D Seal 14B Feedthrough 16, 17, 18 Centrifugal oil compensating piston 19 Piston carrier 20 Gear ring carrier plate 21, 22, 23 Centrifugal oil compensating chambers 27 Opening 30 Gear ring 30A Contact point 30B Feedthrough 30C Installation space 30D Arm K0, K1, K2 Friction clutch A Axle

Claims

1. Assembly with several multiple lamellae clutches with at least two friction clutches (K1, K2, K0) which have lamellae packs disposed so as to be mutually radially offset on lamellae carriers (9, 10, 11, 12), having pistons (13, 14, 15) which serve for actuating the friction clutches (K1, K2, K0), wherein at least the pistons (13, 14) for actuation delimit pressure chambers (40, 41, 42) from centrifugal oil compensation chambers (21, 22, 23), characterized in that at least one of the pistons (13, 14, 15) is produced integrally from sheet metal, and in that the pistons for actuation (13, 14, 15) have seals (13A, 13B, 14A, 14C, 14D) which are vulcanized onto the sheet metal of the pistons for actuation (13, 14, 15), and seal at least the respective pressure chamber (40, 41, 42) in relation to further components of the multiple-lamellae clutch.

2. Assembly with several multiple lamellae clutches according to Claim 1, characterized in that the pistons for actuation (13, 14, 15) have seals (13B, 14C) as sealing lips for sealing off the centrifugal oil compensation chambers (21, 22, 23).

3. Assembly with several multiple lamellae clutches according to Claim 1, characterized in that the pistons for actuation (13, 14, 15) have seals (14D) as running surfaces for the respective centrifugal oil compensation pistons (16, 17, 18).

4. Assembly with several multiple lamellae clutches according to one of the preceding claims, having a gear ring (30) which is attached to a main hub (2) on a gear ring carrier plate (20), characterized in that the gear ring (30) has an installation space (30C) as a pressure chamber, in which the piston (13) for the actuation of the clutch (K0), the latter representing a separating clutch between an internal combustion engine and a transmission, is positioned by way of its radial part and an axial portion.

5. Assembly with several multiple lamellae clutches in the form of an assembly with three multiple lamellae clutches (1) according to one of the preceding claims, having a first, a second and a third friction clutch (K0, K1, K2) which have lamellae packs disposed so as to be mutually radially offset on lamellae carriers (9, 10, 11, 12), having a first piston (13), a second piston (14) and a third piston (15) for actuating the first, the second and the third friction clutch (K0, K1, K2), wherein a first, a second and a third centrifugal oil compensation piston (16, 17, 18), in each case conjointly with the first, the second and the third piston (13, 14, 15) for actuation, forms centrifugal oil compensation chambers (21, 22, 23), wherein the piston (14) of the central clutch (K1) is embodied as an integral sheet-metal component with three seals (14A, 14C, 14D).