Torsional vibration damper with integrated disconnect coupling

Abstract

Torsional vibration damper of a series hybrid powertrain of a vehicle, designed as a dual-mass flywheel installed between an internal combustion engine and an electric motor, wherein the torsional vibration damper (1) comprises a primary part (3) connected to a crankshaft of the internal combustion engine and a multi-part secondary part (4) coupled to an output shaft, which are elastically connected via arc springs (5) inserted in a spring channel (7) and connected to an arc spring flange (10), and the secondary part (4) includes a disconnecting clutch (2), wherein the disconnecting clutch (2), designed as a multi-disc clutch, comprises a clutch basket (12) positioned radially below the spring channel (7) and fixed in position on the arc spring flange (10), which can be coupled to an angled leg (15) of a hub flange (11) of the secondary part (4).wherein, when the disconnect clutch (2) is closed, the disc pack (18) in the clutch basket (12) is subjected to force by a disc spring (20) in conjunction with a deflection lever (21, 34), characterized in that the disc spring (20) is inserted between the hub flange (11) and the deflection lever (21), which is positively supported on the disc pack (18) by means of circumferentially distributed fingers (25) guided through openings (24) of the hub flange (11).

Description

[0001] The invention relates to a torsional vibration damper constructed as a dual-mass flywheel of a series hybrid drive train of a vehicle, which is inserted between an internal combustion engine and an electric motor and comprises a primary part connected to a crankshaft of the internal combustion engine and a multi-part secondary part coupled to an output shaft, which are elastically connected via arc springs inserted in a spring channel and connected to an arc spring flange, and the secondary part includes a disconnecting clutch.

[0002] In P2 hybrid systems, an electric motor (coaxial or parallel to the engine) is installed between the internal combustion engine and the transmission. To allow the electric motor to be used independently of the internal combustion engine for purely electric driving, a disconnect clutch, also known as a KO clutch, is required.

[0003] From WO 2015 / 172 784 A2, a device is known that shows a torque transmission device for hybrid vehicles, which is associated with a powertrain comprising an internal combustion engine, an electric motor, and a transmission. Within the torque transmission device, which includes a disconnect clutch with a clutch actuator, an electric motor is arranged axially offset from a torsional vibration damper.

[0004] Publication WO 2010 / 028 620 A1 shows another torque transmission device for hybrid applications, which includes an internal combustion engine, an electric motor and a dual-mass flywheel, wherein the drives can be switched by means of a disconnect clutch.

[0005] DE 10 2017 130 421 A1 discloses a coupling device for a hybrid module of a motor vehicle with a first lamellar package and with a second lamellar package, which can be selectively switched for torque transmission between a damper unit on the internal combustion engine side and a traction wheel on the electric motor side.

[0006] Further reference is made to DE 10 2009 059 944 A1, DE 10 2010 051 436 A1 and DE 10 2019 109 981 A1 as prior art.

[0007] The invention is based on the objective of presenting a structurally and functionally improved torsional vibration damper with an integrated, high-torque-transmitting disconnect coupling in a cost-effective series production design.

[0008] The aforementioned problem is solved according to the invention by a torsional vibration damper including the features of claim 1. Preferred embodiments of the invention are specified in the dependent claims and the following description.

[0009] According to the invention, the torsional vibration damper comprises a disconnecting clutch designed as a multi-disc clutch, which includes a clutch basket positioned radially below the spring channel and fixed in position on the arc spring flange of the secondary part, which can be coupled to a hub flange of the secondary part with an angled leg.

[0010] The coupling basket, arranged radially below the arc springs or spring channel of the disconnect coupling, which is preferably designed as a conventional multi-plate coupling, is attached to the arc spring flange by force-fit, form-fit, and / or material-fit connection. Together with an angled leg of the hub flange of the secondary part, the coupling basket defines an annular installation space intended for the disconnect coupling.

[0011] In known solutions, the torsional vibration damper is connected, for example, via a splined connection to a disconnect coupling, which is positioned separately from the installation space of the electric motor. Due to the clutch disc, the friction surface and consequently the transmittable torque are limited in these disconnect couplings, making them insufficient for many applications.

[0012] In contrast, the concept according to the invention shows a secondary component in which a multi-disc clutch is integrated between the arc spring flange and the hub flange of the output hub. With the disconnect clutch or the multi-disc clutch, a higher torque from the internal combustion engine can advantageously be transmitted within the same installation space. According to a preferred design, a torque of 400 Nm can be transmitted using the disconnect clutch according to the invention. Due to the direct association of the multi-disc clutch with the secondary component, a space-optimized solution is advantageously achieved, particularly in the radial direction.

[0013] The advantageously space-optimized, simply constructed torsional vibration damper according to the invention, with an integrated, high-torque-transmitting disconnect clutch, can be manufactured cost-effectively. This torsional vibration damper is preferably used for passenger car powertrains, especially for series, series-parallel, and power-split hybrid applications, with separation of the two drives: the internal combustion engine and the electric motor. Furthermore, the concept according to the invention is suitable for implementing P2 hybridization of dual-clutch transmissions, particularly in smaller vehicles with a front-transverse drivetrain, for integration into the available axial installation space.

[0014] According to an advantageous embodiment of the invention, the disengaging clutch comprises a disc assembly housed in the clutch basket, which consists of carrier plates that are alternately connected to the hub flange and the clutch basket in a rotationally secured manner. For rotationally fixed, axially displaceable mounting, guide tracks running parallel to the central axis are provided in the clutch basket and in the angled leg of the hub flange, into which a radial profile of the carrier plates engages in a form-fitting manner. Furthermore, in the disc assembly, also referred to as a lamellar assembly, the carrier plates are each separated by a friction lining, which is attached to a carrier plate by force-fit, form-fit, and / or material-fit connection. The disc assembly also includes a pressure plate on the side facing the curved spring flange.The number of friction linings and consequently associated support plates and pressure plates of the disc pack can be determined depending on the torque to be transmitted.

[0015] When the disconnect clutch, designed as a multi-disc clutch, is engaged, the corresponding disc pack in the clutch basket is pressed against it by at least one diaphragm spring in conjunction with a deflection lever and a pressure plate associated with the disc pack. When the disconnect clutch is disengaged, the force of the diaphragm spring is released, causing the friction linings in the disc pack to slip and thus preventing torque from being transmitted from the internal combustion engine.

[0016] The disc spring used to apply force to the disc assembly is preferably installed between the hub flange and the linkage lever. The disc spring is positioned via recesses in the hub flange and a retaining ring supported on the angled leg of the hub flange. The linkage lever engages the clutch basket with several fingers, for example three, distributed around its circumference and guided through openings in the hub flange. It then applies force to a pressure plate of the disc assembly, moving it towards a closed multi-disc clutch. Instead of several fingers supported at relatively low points, it is advantageous to use a linkage lever that rests directly or parallel to, and thus over a flat surface, against the pressure plate of the disengaging clutch.

[0017] To actuate the multi-disc clutch, a central release bearing, designed as a CSC (Concentric Slave Cylinder), is used, which is connected to the deflection lever via a release bearing. If the release bearing overcomes the force of the disc spring, the friction linings slip and no more torque is transmitted from the internal combustion engine.

[0018] According to a further embodiment of the invention, the secondary part is rotatably mounted by means of a bearing between the hub flange and an output hub associated with the transmission input shaft or the output shaft. A rolling bearing designed as a ball bearing or, alternatively, a plain bearing is preferably suitable for this mounting. The design concept also allows for an alternative secondary part mounting in which a rolling bearing or plain bearing is used between the arc spring flange and a guide element connected to the primary part.

[0019] The torsional vibration damper according to the invention advantageously comprises a sealed spring channel designed for the arc springs. The spring channel, also called the grease chamber, which is at least partially filled with a lubricant, in particular grease, to lubricate the arc springs, is sealed on the output side by means of a disc spring sealing diaphragm. For this purpose, the diaphragm is supported internally on a cover element of the primary part and guided in a pre-tensioned sealing manner against the clutch basket via a friction ring. A friction ring is provided for sealing the spring channel on the drive side; this ring is inserted in an annular gap that is axially limited by the primary part and the arc spring flange.

[0020] The invention is described in more detail below with reference to exemplary embodiments shown in four figures. However, the invention is not limited to the exemplary embodiments shown in the figures. The figures show: Fig. 1: An embodiment of a torsional vibration damper according to the invention in a half section; Fig. 2: a section contour of Fig. 1 in an enlarged view showing an alternative support of the deflection lever on the disc pack; Fig. 3: a section contour of Fig. 1 in an enlarged view showing an alternative arrangement of the disc spring sealing membrane; Fig. 4: a section outline of Fig. 1 in an enlarged view showing an alternative storage of the secondary part.

[0021] The Fig. Figure 1 shows a half-section of the basic structure of a torsional vibration damper 1 with an integrated disconnect clutch 2, which is intended in particular for a series hybrid powertrain (not shown) of a motor vehicle. The torsional vibration damper 1, also called a dual-mass flywheel (DMF), comprises on the input side a multi-part primary part 3 connected to a crankshaft of the internal combustion engine (not shown) and a secondary part 4 consisting of several components connected to an output, for example a transmission shaft (not shown). The primary part 3 and the secondary part 4 are arranged to be rotatable together about an axis of rotation and to be rotatable relative to each other within limits, with the primary part 3 being connected to the secondary part 4 via a damping device 6 enclosing arc springs 5.The arc springs 5 ​​are arranged circumferentially in a spring channel 7 filled with lubricant, in particular grease, which is bounded by the primary part 3 and a cover element 8 that is bonded to the primary part 3. Each arc spring 5 is supported at one end against a stop (not shown) of the primary part 3 and at the other end against a flange wing 9 of an arc spring flange 10, which together with a hub flange 11 forms the secondary part 4.

[0022] The disconnect clutch 2, integrated into the torsional vibration damper 1, allows the internal combustion engine to be disconnected from the drivetrain in an electric vehicle. The disconnect clutch 2, designed as a multi-disc clutch or lamellar clutch and associated with the secondary part 4, is positioned radially below the spring channel 7. The disconnect clutch 2 comprises a clutch basket 12, which is fixed to the curved spring flange 10. This clutch basket can be coupled to an angled leg 15 of the hub flange 11 via carrier plates 13 (also called lamellae) in conjunction with friction linings 14, which together form a disc pack 18. The axially displaceable support plates 13 engage alternately in a form-fitting manner, each separated by a friction lining 14, in guide tracks 16, 17 of the clutch basket 12 and the leg 15. The disc pack 18 also has a pressure plate 19 assigned to it on the side facing the arc spring flange 10.

[0023] With the multi-disc clutch or disconnect clutch 2 engaged, the disc assembly 18 is axially actuated by a Belleville spring 20 via a deflection lever 21, also called an actuating plate. The Belleville spring 20 is axially supported between a retaining ring 22 of the deflection lever 21 and a bore 23 of the hub flange 11. The deflection lever 21 is supported on the pressure plate 19 by circumferentially distributed fingers 25, which are guided through openings 24 in the hub flange 11. To actuate, to release the disconnect clutch 2, a hydraulically actuated release cylinder 26, designed as a CSC (Concentric Slave Cylinder), is used, which displaces the deflection lever 21 in the direction of the arrow via a release bearing 27. This disengages the frictional connection of the disc assembly 18, causing the friction linings 14 or their backing plates 13 to slip.

[0024] A relative rotation between the primary part 3 and the secondary part 4 enables a rolling bearing 28 between the hub flange 11 and an output hub 29, which is connected, for example, to an output shaft or transmission shaft (not shown). To prevent lubricant loss from the spring channel 7, it is sealed. A disc spring sealing diaphragm 30 is provided for the output-side sealing of the spring channel 7. This diaphragm is pre-tensioned and supported on the inside of the cover element 8 of the primary part 3 and on the clutch basket 12 via a friction ring 31. On the input side, a friction ring 32 is inserted in an annular gap 33, axially limited by the primary part 3 and the curved spring flange 10, to seal the spring channel 7.

[0025] In the Fig. 2 to Fig. Figure 4 shows alternative or different embodiments of individual components of the torsional vibration damper 1. Fig. 2 shows a deviation from Fig. 1. The deflection lever 34 is designed and is directly supported on the friction ring 14 without a pressure plate. The deflection lever 34 has a straight section at its end, running parallel to the friction ring 14, thus ensuring a large-area support. According to Fig. 3 is the disc spring sealing membrane 35, which differs from the one in Fig. The solution shown in Figure 1 is positioned above the attachment of the clutch basket 12 to the arc spring flange 10. Fig. 4 the bow spring flange 10 of the secondary part 4 is rotatably mounted on a guide element 37 connected to the primary part 3 via the bearing 36. Reference symbol list 1 torsional vibration damper 2 Disconnect coupling 3 Primary part 4 Secondary part 5 Bow feather 6 Damping device 7 spring channel 8 lid element 9 flange wings 10 Bow spring flange 11 Hub flange 12 Clutch basket 13 Carrier plate 14 friction lining 15 thighs 16 Guide rail 17 Guide rail 18-inch disc package 19 Pressure plate 20 Belleville washers 21 Deflection lever 22 retaining ring 23 bore 24-hour opening 25 fingers 26 deployment vehicles 27 Release bearing 28 Storage 29 Output hub 30 Disc spring sealing membrane 31 friction ring 32 friction ring 33 Annular gap 34 Deflection levers 35 Disc spring sealing membrane 36 Storage 37 Guide element

Claims

Torsional vibration damper of a series hybrid powertrain of a vehicle, designed as a dual-mass flywheel installed between an internal combustion engine and an electric motor, wherein the torsional vibration damper (1) comprises a primary part (3) connected to a crankshaft of the internal combustion engine and a multi-part secondary part (4) coupled to an output shaft, which are elastically connected via arc springs (5) inserted in a spring channel (7) and connected to an arc spring flange (10), and the secondary part (4) includes a disconnecting clutch (2), wherein the disconnecting clutch (2), designed as a multi-disc clutch, comprises a clutch basket (12) positioned radially below the spring channel (7) and fixed in position on the arc spring flange (10), which can be coupled to an angled leg (15) of a hub flange (11) of the secondary part (4).wherein, when the disconnect clutch (2) is closed, the disc pack (18) in the clutch basket (12) is acted upon by a disc spring (20) in conjunction with a deflection lever (21, 34), characterized in that the disc spring (20) is inserted between the hub flange (11) and the deflection lever (21), which is positively supported on the disc pack (18) by means of circumferentially distributed fingers (25) guided through openings (24) of the hub flange (11). Torsional vibration damper according to claim 1, characterized in that a disc pack (18) is incorporated in the clutch basket (12) of the disconnecting clutch (2), consisting of carrier plates (13) which are alternately connected to the hub flange (11) and the clutch basket (12) in a rotationally fixed manner and are each separated by a friction lining (14) and the disc pack (18) includes a pressure plate (19) on the arc spring flange side. Torsional vibration damper according to claim 2, characterized in that a friction lining (14) is attached to a carrier plate (13) by force, form and / or material connection. Torsional vibration damper according to one of the preceding claims, characterized in that a release bearing (26) designed as a CSC (Concentric Slave Cylinder) is used to actuate the disconnect clutch (2), which is connected to the deflection lever (21, 34) via a release bearing (27). Torsional vibration damper according to one of the preceding claims, characterized in that the secondary part (4) is rotatably mounted on an output shaft by means of a bearing (28) between the hub flange (11) and an output hub (29). Torsional vibration damper according to one of the preceding claims, characterized in that the secondary part (4) is rotatably mounted by means of a bearing (36) between the arc spring flange (10) and a guide element (37) connected to the primary part (3). Torsional vibration damper according to one of the preceding claims, characterized in that a disc spring sealing membrane (30, 35) is provided for the output-side sealing of the spring channel (7), which is supported on the inside of the cover element (8) of the primary part (3) and is guided in a pre-tensioned sealing manner via a friction ring (31) on the clutch basket (12). Torsional vibration damper according to one of the preceding claims, characterized in that a friction ring (32) is inserted in an annular gap (33) between the primary part (3) and the arc spring flange (10) for the drive-side sealing of the spring channel (7).

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