TORSIONAL VIBRATION DAMPER WITH A ROTATIONAL AXIS FOR A DRIVETRAIN

Description

[0001] The present invention relates to a torsional vibration damper with a rotation axis for a drive train.

[0002] Torsional vibration dampers are known from the prior art; they are used in a drive train, for example in a motor vehicle, to mitigate the effects of torque fluctuations. Motor vehicle drive trains must also be protected from excessive torque peaks, and due to the increasing degree of electrification of motor vehicle drive trains, their sensitivity to such excessive torque peaks is increasing. For this purpose, a torque limiter is integrated into the torsional vibration damper. The torsional vibration damper also includes a damper for torque fluctuations. In torsional vibration dampers with a hub flange, increased wear of the helical compression springs occurs, which initially leads to a deterioration in the performance of the damper (noise) and ultimately to the fracture of the helical compression spring. To reduce wear, multi-hub flanges with two or more flanges are used.This has the advantage that the compression ends of the helical compression springs are attached exclusively to the flanges, and the side plates are connected via the flanges in a torque-transmitting manner, for example, using bolts. Furthermore, the helical compression springs can be guided via the flanges.

[0003] The document US 2005 / 076739 A1 is considered to be the closest prior art.

[0004] Based on this, the present invention seeks to at least partially overcome the disadvantages known from the prior art. In particular, the mass moment of inertia of the torsional vibration damper on the output side or the transmission side is to be reduced.

[0005] According to the invention, this object is achieved by a torsional vibration damper according to claim 1 with a rotation axis for a drive train, comprising at least the following components: a multi-flange damper with a plurality of flanges for the shear torque-dependent and tensile torque-dependent damping of torsional vibrations; a torque limiter unit arranged radially inside the multi-flange damper and having inner and outer plates for limiting a maximum transmittable torque; an outer hub arranged radially inside the multi-flange damper and radially outside the torque limiter unit, which connects the multi-flange damper to the torque limiter unit in a torque-transmitting manner; and an inner hub arranged radially inside the torque limiter unit for connection to a transmission input shaft, wherein the outer hub has an external toothing which is in alternating engagement with the flanges of the multi-flange damper in a shear torque-dependent and tensile torque-dependent manner, and wherein the outer hub has an internal toothing into which the outer plates of the torque limiter unit are suspended.

[0006] Preferred embodiments are set out in the dependent claims.

[0007] In the following, reference is made to the specified axis of rotation whenever, without explicit indication to the contrary, the axial direction, radial direction, or the direction of rotation and corresponding terms are used. Ordinal numbers used in the preceding and following descriptions serve only to clearly distinguish them and do not reflect the order or ranking of the designated components. An ordinal number greater than one does not necessarily imply that another such component must be present.

[0008] The torsional vibration damper proposed here is designed to mitigate torsional vibrations and torque peaks in a drive train, preferably in an electrified drive train, while achieving high wear resistance in a small installation space. The torsional vibration damper proposed here comprises a multi-flange damper for damping torsional vibrations, which comprises two or more flanges, often referred to as hub flanges. These flanges are elastically preloaded relative to one another by means of energy storage elements, for example helical compression springs or arc springs, so that a torque can be transmitted from one flange to the other flange solely by means of the energy storage element. In a preferred embodiment, three or more flanges are provided, with a first (hub) flange being arranged on the engine side and being designed to directly absorb an engine-side torque.On the opposite side, a transmission-side (hub) flange is provided, which is directly connected to a hub for connection to a transmission input shaft in a torque-transmitting manner. Between these two hub flanges, at least one (center) flange is provided, which is elastically connected to the two hub flanges solely via at least one energy storage element on the hub flange side. The two hub flanges are not in direct torque-transmitting contact with each other.

[0009] Furthermore, a torque limiter unit is provided, which is configured to transmit a predetermined maximum torque and opens when the applied torque exceeds the predetermined maximum torque (torque overshoot). Thus, this maximum transmittable torque is the maximum seen by the other side of the torque limiter unit.

[0010] Here, it is proposed that the torque limiter unit be arranged on the transmission side so that the multi-flange damper is not subjected to a torque exceeding the maximum transmittable torque. Thus, the multi-flange damper is protected from such (wear-causing) loads. The torque limiter unit is arranged between an inner hub and an outer hub, with the inner hub being directly connected to the transmission input shaft via a transmission input shaft or another intermediate element (such as a clutch or a dual-mass flywheel).

[0011] The outer hub is designed so that the multi-flange damper is in direct torque-transmitting contact with this outer hub. Particularly preferably, the outer hub is designed towards the multi-flange damper such that the flanges of the multi-flange damper are centered on the outer hub. The torque limiter unit is provided between the outer hub and the inner hub. If, for example, the torque limiter unit is designed as a multi-plate limiter with outer plates and inner plates, the outer plates are suspended in the outer hub and the inner plates in the inner hub. In such an embodiment of the torque limiter unit as a multi-plate limiter, the outer plates are preferably designed as friction linings and the inner plates as metallic (e.g., steel) plates, preferably without friction linings.

[0012] Preferably, the torque limiter unit comprises a preloading means and a counterbearing, between which the inner and outer plates are arranged alternately in the axial direction to limit the maximum torque that can be transmitted between the inner hub and the outer hub. The preloading means and the counterbearing are axially supported on the outer hub.

[0013] Furthermore, it is advantageous if the preloading means and the counter bearing are arranged radially inside the outer hub.

[0014] Preferably, the counterbearing is formed integrally with the outer hub, and the preloading means is axially supported in the outer hub by means of a retaining ring. Alternatively, the counterbearing is formed by means of a retaining ring, and the preloading means is axially supported by means of a one-piece inner shoulder of the outer hub.

[0015] It is proposed that the preloading means for the torque limiter unit and the opposing counterbearing are each axially supported on the outer hub. For example, the preloading means is a disc spring (or a disc spring assembly) and the counterbearing is a ring. The friction partners of the torque limiter unit are pressed together against the counterbearing by the preloading means in such a way that a maximum predetermined torque can be transmitted. If this predetermined torque is exceeded (torque overshoot), the friction partners lift off from each other, and part of the applied torque is dissipated as waste heat.

[0016] The proposed design of the torsional vibration damper exhibits a particularly low transmission-side mass moment of inertia because the torque limiter unit is located entirely radially inside the outer hub. Thus, if the torque limiter unit slips, only the inner hub (including the inner plates, if applicable) is moved along. The preloading device and the counterbearing are also supported on the outer hub and are therefore not moved along.

[0017] In a preferred embodiment, the outer hub is designed as a machined component, for example, by turning and / or shaping. Such a component is very compact and can be manufactured with high strength, while also being cost-effective. In another embodiment, the outer hub is produced by sintering or by (preferably cold) extrusion. Other manufacturing processes can also be used, although the selection should be based on mechanical requirements, quantity, and a given cost framework. In one embodiment, the inner hub is manufactured in the same way as the outer hub.

[0018] In a preferred embodiment of the outer hub, the number of (internal) teeth of the internal gearing is greater than the number of (external) teeth of the external gearing. Particularly preferably, the number of internal teeth corresponds to a multiple of the number of external teeth. This achieves a favorable stress distribution in the outer hub.

[0019] It is advantageous if the multi-flange damper has at least one stop with which one of the flanges can come into contact during shear torque transmission, and with which another of the flanges can come into contact during tensile torque transmission, whereby the contact of the respective flange against the stop is free of play, while the simultaneous engagement of the respective flange with the outer hub is subject to play. The multi-flange damper is therefore floating on the outer hub. In this context, "with play" in the sense of a floating bearing means a play in the toothing that is greater than 0.0 mm and less than 0.5 mm, which can compensate for manufacturing tolerances and prevent rattling noises. If, on the other hand, the contact of the flange against the stop were subject to play, this would lead to rattling noises.

[0020] The torsional vibration damper proposed here corresponds, at least functionally, to the previously described torsional vibration damper, with the preloading means and the counterbearing of the torque limiter unit being optionally supported in the outer hub. Here, it is proposed that, alternatively or in addition to the preceding description, the torsional vibration damper have an outer hub configured such that the flanges of the multi-flange damper are mounted in a floating manner on the outer hub. Because the flanges of the multi-flange damper are mounted in a floating manner on the outer hub, the flanges are freed from the forces required to preload the components of the torque limiter unit and can move solely according to the conditions prevailing in a multi-flange damper, and the components of the multi-flange damper are subjected to a correspondingly (light) load.This is particularly advantageous if a hysteresis element is additionally provided (as suggested below), because the hysteresis element is not subjected to forces originating from the torque limiter unit or its preloading means.

[0021] In this design, both the preloading element and the counter bearing are supported on the outer hub, and the multi-flange damper is mounted floatingly on the outer hub. This results in a compact and simple design with the aforementioned advantage of low loading on the multi-flange damper.

[0022] It is further proposed in an advantageous embodiment of the torsional vibration damper that the counter bearing is formed integrally with the outer hub and the preloading means is axially supported by means of a retaining ring in the outer hub or the counter bearing is formed by means of a retaining ring and the preloading means is axially supported by means of a one-piece inner shoulder of the outer hub, wherein preferably the outer hub is designed as a machined component, wherein preferably the outer hub has an outer shoulder with which a hysteresis element is formed together with one of the flanges.

[0023] In a first embodiment, it is proposed that the counterbearing be formed integrally with the outer hub, i.e., it does not have to be connected to the outer hub as a separate component, but is already formed integrally with the outer hub during assembly of the torsional vibration damper. It is not excluded that the counterbearing was first connected to the outer hub in a pre-assembly step, for example by welding. Furthermore, it is proposed that the preloading means be supported by a retaining ring, which, for example, is designed as a spring washer, is tensioned radially outward and can be inserted into a corresponding groove in the outer hub.

[0024] Here, in a second (alternative) embodiment, it is proposed that the counterbearing be formed by a retaining ring which, for example, is tensioned radially outwards and can be inserted and supported in a corresponding groove in the outer hub. Furthermore, an inner shoulder (directed radially inwards) is formed integrally with the outer hub, i.e., it does not have to be connected to the outer hub as a separate component, but is already formed integrally by the outer hub during assembly of the torsional vibration damper. It is not excluded that the inner shoulder has first been connected to the outer hub in a pre-assembly step, for example by welding. The preloading means is axially supported on this inner shoulder.

[0025] For example, in an embodiment of the torque limiter unit as a multi-plate limiter, the plates can be inserted into the outer hub (and the inner hub) in the desired order (in both of the aforementioned embodiments), and the preloading means or counterbearing can then be attached. The reaction force is axially supported by the retaining ring in the outer hub to maintain the desired preload. The inner hub merely provides a positional lock, such as a floating bearing, to the torque limiter unit (or possibly the inner plates). In the event of excessive torque, only the inner friction partner (such as the inner hub with the inner plates) rotates on the transmission side, so that the transmission-side mass moment of inertia (at least relative to the torsional vibration damper) is particularly low.

[0026] In a preferred embodiment, the outer hub has an outer shoulder, which is configured as an axial contact for a hub flange of the multi-flange damper. This axial contact is particularly preferably designed with a predetermined preload and a predetermined coefficient of friction, optionally with a friction lining arranged therebetween, so that a hysteresis element is formed (see the following explanations). In another embodiment, the external toothing of the outer hub is designed with at least one axial end face, preferably two axial end faces, by means of which an axial contact is formed for the multi-flange damper, preferably with both or one of the side plates, for example in the embodiment described below.

[0027] It is further proposed in an advantageous embodiment of the torsional vibration damper that a pre-damper is provided on the inner hub side and / or the outer hub side.

[0028] Here, it is proposed that the torsional vibration damper further comprise at least one pre-damper, for example to counteract knocking noises during a rapid coupling operation when idling or a similar situation in a drive train. In one embodiment, a pre-damper is provided for each of the two torque directions (referred to in the motor vehicle as the tensile torque and the shear torque). In one embodiment, a single pre-damper is provided, which is preferably arranged such that it is effective for both torque directions, for example on the center flange that may be provided. In one embodiment, at least one of the pre-dampers is arranged in front of or on the inner hub, in front of or on the outer hub, or in front of or on one of the (hub) flanges.

[0029] It is further proposed in an advantageous embodiment of the torsional vibration damper that at least three flanges are connected in series with each other.

[0030] In this embodiment, the at least three flanges are connected in series with one another in that the flanges are supported via energy storage elements on the flange immediately adjacent in the direction of rotation (or in the direction of the angle of rotation). A rotational irregularity is thus first transmitted to a first (hub) flange, then to a (center) flange immediately adjacent in the direction of rotation, and from the (center) flange immediately adjacent in the direction of rotation to the (hub) flange immediately adjacent in the direction of rotation (and continued accordingly if there are more than three flanges). Depending on the direction of the torque impact, this applies accordingly starting from the engine side, from the gearbox side, or from the torque limiter unit side.Preferably, the hub flanges are connected (radially inside) to the outer hub and (radially outside) to the at least one side disc in a torque-transmitting manner according to the following description, and the at least one central flange is supported solely on the hub flanges in a torque-transmitting manner and is preferably centered by means of the outer hub. A staggered response behavior of the flanges is particularly preferably established by arranging a softer energy storage element between the first (hub) flange and the at least one central flange and a comparatively harder energy storage element between the second (hub) flange and the at least one central flange. The energy storage elements are preferably each helical compression springs, for example spring assemblies with at least one inner spring and one outer spring. Particularly preferably, the helical compression springs are all designed with straight spring axes.

[0031] It is further proposed in an advantageous embodiment of the torsional vibration damper that at least one centrifugal pendulum is provided, wherein preferably at least one of the centrifugal pendulums is fixed to an axially central flange of at least three flanges.

[0032] Often, high noise emissions from a motor vehicle are undesirable. For this purpose, it is advantageous to provide a centrifugal pendulum absorber. The centrifugal pendulum absorber is connected to the torsional vibration damper as proposed here, allowing predetermined vibration frequencies of the transmitted torque to be eliminated. The centrifugal pendulum absorber is preferably located on the engine side of the (outer) hub, i.e., on the multi-flange damper. This ensures a particularly low mass moment of inertia on the transmission side.

[0033] In a preferred embodiment, the centrifugal pendulum absorber is attached to a center flange, so that, on the one hand, the load on the hub flange is low and, on the other hand, the noise-generating frequencies are eliminated particularly early on the motor side. A further advantage is that a centrifugal pendulum absorber on the center flange is always active during operation because the center flange is always free, thus actively participating in damping, while a hub flange is firmly attached in a corresponding torque direction. In another embodiment, a centrifugal pendulum absorber is fixed to at least one of the hub flanges, so that a specific torque-direction-dependent absorption is set.

[0034] It is further proposed in an advantageous embodiment of the torsional vibration damper that the multi-flange damper comprises at least one helical compression spring with a straight spring axis between the plurality of flanges, wherein preferably the at least one helical compression spring is guided radially only by at least one of the flanges.

[0035] Here, it is proposed that the multi-flange damper comprise at least one helical compression spring with a straight spring axis, preferably a total of four helical compression springs, each with a straight spring axis, two of which are arranged between a first hub flange and a center flange, and two between the center flange and the other hub flange of a total of three flanges of the multi-flange damper. Such a design allows for a compact structure and long torsion angles, thus enabling large torque deflections while maintaining the damping properties of the multi-flange damper. At the same time, helical compression springs with straight spring axes are easy to control in terms of their damping properties and cost-effective to manufacture.

[0036] In a preferred embodiment, the at least one helical compression spring is guided radially solely by at least one of the flanges, particularly preferably by means of a centering lug on each of the two flanges to which the respective helical compression spring is attached. In this case, there is preferably no contact with other components of the multi-flange damper or the torsional vibration damper. This minimizes wear on the helical compression spring.

[0037] In a preferred embodiment, the at least three flanges are connected in series with one another, preferably by means of the aforementioned helical compression springs, in that a softer helical compression spring is arranged between the first (hub) flange and the at least one middle flange and a comparatively harder helical compression spring is arranged between the second (hub) flange and the at least one middle flange.The helical compression springs are preferably at least partially designed as spring assemblies, wherein in one embodiment at least one (preferably the inner) spring of the spring assembly is shorter than the longest spring of the spring assembly (preferably not preloaded, particularly preferably spaced from one of the adjacent flanges), so that initially only the (permanently brought into contact and tensioned) longest spring is in contact with the two adjacent flanges and only from a predetermined relative angle of rotation of the adjacent flanges does the at least one shorter spring become effective. In this way, a stepped spring stiffness is created using simple means. Particularly preferably, the outermost spring of the spring assembly is centered, for example by means of a pin or cup, and the at least one inner spring is guided by means of the outermost spring.In one embodiment, for example, a (single) outer helical compression spring and a (single) inner helical compression spring are provided. The outer helical compression spring is guided and centered, and the inner helical compression spring is guided by the outer helical compression spring. The inner helical compression spring is so much shorter than the outer helical compression spring that, in the non-compressed state of the outer helical compression spring, the inner helical compression spring is in contact only with one flange or no flange at all, preferably being attached to a flange, for example, the center flange.The inner helical compression spring is only in contact with the other flange, for example one of the hub flanges, when the two flanges are rotated against each other by such an angle that the distance covered corresponds to the length difference of the two helical compression springs of the spring assembly described here or (then with a force transmission of the inner helical compression spring) is greater than this length difference.

[0038] It is further proposed in an advantageous embodiment of the torsional vibration damper that at least one side disc is provided for connection to a drive shaft, wherein the at least one side disc is connected on the connection side to the multi-flange damper in a torque-transmitting manner, wherein preferably the at least one side disc is spaced apart from the at least one helical compression spring according to an embodiment according to the above description during operation of the torsional vibration damper.

[0039] In this embodiment, it is proposed that at least one side plate, particularly preferably two side plates as a pair, are provided axially laterally of the flanges of the multi-flange damper, wherein the side plate is designed, preferably indirectly, for connection to a drive shaft. For example, the first of two paired side plates is equipped with a radially outwardly projecting flange, which can be connected, preferably screwed, to a flywheel of a drive shaft. The second side plate of two side plates does not have such a radial flange and is particularly preferably arranged axially overlapping the connection of the first side plate to the drive shaft, for example the flywheel. The at least one side plate has a stop, preferably the two side plates have a bolt or a rivet plate, which can be brought into torque-transmitting contact with the hub flanges in the circumferential direction.

[0040] In a preferred embodiment, the at least one side window is arranged such that, under a design load, the helical compression spring is always spaced from the side window, so that no frictional engagement is formed between the side window and the at least one helical compression spring. It should be noted that preferably, no friction-reducing means is provided between the side window and the helical compression spring, but rather an air gap is provided. For example, the at least one side window is configured such that the escape of an overloaded, e.g., broken, helical compression spring can be prevented by the side window, so that surrounding components are protected in the event of a disaster.

[0041] The side window is preferably a sheet metal component, which is particularly preferably formed by cold forming, for example embossing and / or punching.

[0042] It is further proposed in an advantageous embodiment of the torsional vibration damper that at least one hysteresis element is formed between the at least one side disc and one of the flanges, wherein preferably under axial hysteresis preload a first flange is in frictional contact with a first side disc by means of a friction lining and a second flange is in direct frictional contact with a second side disc.

[0043] Here, it is proposed that at least one hysteresis element is further formed, whereby the response behavior of the multi-flange damper can be delayed. Thus, a respective flange is only set into vibration above a predetermined torque amplitude, and below this predetermined torque amplitude, the corresponding flange remains in its initial position. In a preferred embodiment, the multi-flange damper has two hub flanges, wherein each hub flange is preferably designed with a separate, particularly preferably differently configured, hysteresis element. Particularly preferably, a single preloading means is provided for both hysteresis elements, wherein the preloading means is, for example, a disc spring (or a disc spring assembly) or is formed by means of an installation situation, for example by riveting.

[0044] In a preferred embodiment, a friction lining is provided between the first side plate and a first flange, forming a first hysteresis element, and a direct contact is formed between the second side plate and the second flange, forming a second hysteresis element. With direct frictional contact between the second flange and the second side plate, the coefficient of friction is low (e.g., metal on metal). This is particularly suitable in a motor vehicle for the so-called thrust direction, i.e., the transmission of a (e.g., wheel) torque to the drive engine (see below). For the pull direction in a motor vehicle, however, a higher coefficient of friction is advantageous, whereby a higher torque amplitude is necessary to trigger the action of the multi-flange damper. The use of a friction lining in the hysteresis element is advantageous here.

[0045] It is further proposed in an advantageous embodiment of the torsional vibration damper that the multi-flange damper comprises three or more axially adjacent flanges and that the at least one axially central flange is centered on the outer hub and is axially supported by two axially adjacent flanges, preferably by means of a low-friction centering element.

[0046] In this embodiment, it is proposed that the multi-flange damper comprises three or more axially adjacent flanges, with at least one axially central flange (center flange) being formed. This axially central flange is centered on the outer hub, but not in torque-transmitting contact with the outer hub. Only the two hub flanges are configured to transmit torque (dependent on the direction of the torque) with the outer hub and are also centered via the outer hub. Thus, the flanges of the multi-flange damper are all centered relative to the outer hub.

[0047] In a preferred embodiment, the at least one axially central flange is provided with a centering element, which ensures low-friction contact with the outer hub and / or the axially adjacent flanges. Such a centering element is preferably a plastic part that is clicked onto the at least one axially central flange in a form-fitting manner or is injection-molded onto the flange. In a particularly preferred embodiment, the clearance between the outer hub and the centering element is particularly small, and most preferably, the centering element has run-in properties so that production-related deviations can be compensated for during operation.

[0048] According to a further aspect, a drive train is proposed, comprising at least the following components: an electric drive machine with a drive shaft; at least one consumer; and a torsional vibration damper according to an embodiment as described above, wherein the drive shaft for transmitting torque is connected to the at least one consumer in a vibration-damped and frictionally limited manner to a predetermined maximum torque by means of the torsional vibration damper.

[0049] The drive train proposed here comprises an electric drive motor, which is connected to at least one consumer, for example, the drive wheels in a motor vehicle, in a torque-transmitting, preferably separable, manner. The torsional vibration damper protects the electric drive motor from excessive torque (on the consumer side) and dampens torque fluctuations (at least induced by the consumer side), thus effectively protecting the sensitive electric drive motor. The inner hub is located on the consumer side, and the multi-flange damper (for example, by means of at least one of the side discs) is located on the engine side.

[0050] The drive train proposed here is particularly well damped against torsional vibrations and the drive machine is protected from excessive torque on the transmission side, whereby the load on the transmission components of the drive train is particularly low due to the low transmission-side mass moment of inertia.

[0051] According to a further aspect, a motor vehicle is proposed, comprising at least one drive wheel which can be driven by means of a drive train according to an embodiment according to the above description.

[0052] Installation space is particularly limited in motor vehicles due to the increasing number of components, making it particularly advantageous to use a compact drivetrain. With the use of an electric drive motor, the sensitivity to disruptive torque fluctuations and torque peaks is high, so effective damping of such torque fluctuations and a good limitation of the maximum transmittable (wheel-side) torque are desirable.

[0053] The torsional vibration damper proposed here is a cost-effective component requiring little installation space, which has a long service life and is designed to be extremely gentle on the transmission due to the low moment of inertia on the transmission side.

[0054] The invention described above is explained in detail below against the relevant technical background with reference to the accompanying drawings, which show preferred embodiments. The invention is in no way limited by the purely schematic drawings, whereby it should be noted that the drawings are not to scale and are not suitable for defining proportions. It is shown in Fig. 1: a torsional vibration damper in section; Fig. 2: a torsional vibration damper with a centrifugal pendulum; Fig. 3: a torsional vibration damper with a centrifugal pendulum in a further embodiment; Fig. 4: a circuit diagram of a torsional vibration damper without a pre-damper; Fig. 5: a circuit diagram of a non-stressed torsional vibration damper with an outer hub-side pre-damper; Fig. 6: a circuit diagram of a torsional vibration damper with an inner hub-side pre-damper; Fig. 7a: the torsional vibration damper from Fig. 1 in section, in which the torque flow in traction operation is entered; Fig. 7b: the torsional vibration damper from Fig. 1 in a plan view showing the torque flow in traction operation at half the angle of rotation; Fig. 7c: the torsional vibration damper from Fig. 1 in a plan view showing the torque flow in traction operation at full torsion angle; Fig. 8a: the torsional vibration damper from Fig. 1 in section, in which the torque flow in overrun mode is entered; Fig. 8b: the torsional vibration damper from Fig. 1 in a plan view showing the torque flow in overrun mode at half the angle of rotation; Fig. 8c: the torsional vibration damper from Fig. 1 in a plan view showing the torque flow in overrun mode at full angle of rotation; Fig. 9: the torsional vibration damper from Fig. 1 in a plan view; and Fig. 10: a drive train with a torsional vibration damper in a motor vehicle.

[0055] In Fig. 11 is a schematic diagram of a torsional vibration damper 1 with a rotational axis 2 in section on a transmission input shaft 9 (shown in dashed lines). The torsional vibration damper 1 comprises a multi-flange damper 4 and a centrally arranged torque limiter unit 11. The multi-flange damper 4 comprises a helical compression spring 20 with a straight spring axis 21 and three flanges, namely a (first) hub flange 5 (on the right as shown), a (second) hub flange 6 (on the left as shown), and an axially central (center) flange 7. The hub flanges 5, 6 are connected in a direction-dependent manner to the external toothing 31a of the outer hub 10 in a torque-transmitting manner. The center flange 7 is centered on the outer hub 10, here optionally by means of a centering element 26 and on the external toothing 31a. The centering element 26 is preferably made of a friction-reducing plastic.Two side plates 22, 23 are provided on the torsional vibration damper 1, located laterally of the flanges 5, 6, 7 of the multi-flange damper 4, with a first side plate 22 being configured for connection to a drive shaft 24 of a drive train 3. The side plates 22, 23 are (optionally) designed as sheet metal elements. To protect the motor vehicle 30 from torque increases during operation, the torsional vibration damper 1 has a torque limiter unit 11. The torque limiter unit 11 is arranged between an inner hub 8 and an outer hub 10. The torque limiter unit 11 comprises a plate pack with a plurality of inner plates 32 and outer plates 33, each of which is designated pars-pro-toto here.The outer plates 33 are suspended in the outer hub 10 and the inner plates 32 in the inner hub 8, wherein the outer plates 33 are preferably formed as friction linings 25 and the inner plates 32 as metal plates (for example, made of steel). To generate the predetermined preload on the plate pack, a preloading means 12 is provided, which here is designed as a disc spring (or as a disc spring assembly). The preloading means 12 and the antagonistic counterbearing 13 are each (antagonistically) axially supported on the outer hub 10. The counterbearing 13 is here (optionally) formed by a retaining ring 14 supported on the outer hub 10. The preloading means 12 is (optionally) supported on an inner shoulder 15 formed integrally with the outer hub 10, wherein the inner shoulder 15 is preferably formed by punching from a tubular blank from which the outer hub 10 is formed (by machining).Furthermore, a hysteresis element 17 is (optionally) provided on each of the two hub flanges 5, 6. One hysteresis element 17 is formed between the second hub flange 6 and the axially equilateral (second) side plate 23, with a friction element 34 interposed. Another hysteresis element 17 is formed between the first hub flange 5 and an outer shoulder 16 of the outer hub 10. The first side plate 22 is centered on the outer hub 10 (optionally by means of a centering sleeve 35) and forms a contact surface with the outer shoulder 16.

[0056] The external toothing 31a of the outer hub 10 is in alternating engagement with the flanges 5, 6, 7 of the multi-flange damper 4, depending on the thrust torque and the tensile torque. Furthermore, the outer hub 10 has an internal toothing 31b, into which the outer plates 33 of the torque limiter unit 11 are suspended. The multi-flange damper 4 has at least one stop 50, with which one of the flanges 5, 6, 7 can engage during thrust torque transmission, and with which another of the flanges 5, 6, 7 can engage during tensile torque transmission. The engagement of the respective flange 5, 6 with the stop 50 is free of play, while the simultaneous engagement of the respective flange 5, 6 with the outer hub (particularly at the full angle of rotation) is subject to play.The inner plates 32 and the outer plates 33 are arranged alternately in the axial direction between the preloading means 12 and the counterbearing 13 to limit the maximum torque that can be transmitted between the inner hub 8 and the outer hub 10. The preloading means 12 and the counterbearing 13 are axially supported on the outer hub 10. Furthermore, the preloading means 12 and the counterbearing 13 are arranged radially inside the outer hub 10. The counterbearing 13 is formed integrally with the outer hub 10, and the preloading means 12 is axially supported in the outer hub 10 by means of a retaining ring 14. Alternatively, the counterbearing 13 is formed by means of a retaining ring 14, and the preloading means 12 is axially supported by means of the integral inner shoulder 15 of the outer hub 10.

[0057] In Fig. 2is a schematic diagram of a torsional vibration damper 1 with a rotation axis 2 in section on a transmission input shaft 9 (shown in dashed lines). The torsional vibration damper 1 is similar to that in Fig. 1described and in this respect reference is made to the description therein. The side plates 22, 23 are axially mounted here by means of the external toothing 31a of the outer hub 10, namely the first side plate 22 in contact with a first axial end face 36 of the external toothing 31a and the second side plate 23 in contact with a second axial end face 37 of the external toothing 31a. The torsional vibration damper 1 here comprises (independently of the aforementioned mounting of the side plates 22, 23) a centrifugal pendulum absorber 19, which is preferably suspended from the central flange 7. The centrifugal pendulum absorber 19 is arranged axially laterally, preferably on the transmission side, in radial overlap with the first side plate 22 (and here also the radially smaller second side plate 23). Two hysteresis elements 17 are provided (independently of the aforementioned).One hysteresis element 17 comprises a hysteresis preloading means 38 and a friction lining 25, wherein the hysteresis preloading means 38 is designed here as a disc spring or diaphragm spring (or spring assembly) and is supported directly on the first side plate 22. The corresponding friction lining 25 is frictionally supported or attached to the first hub flange 5 (and is in frictional contact with the hysteresis preloading means 38). The other hysteresis element 17 is formed by direct (metallic) contact between the second side plate 23 and the second hub flange 6.Preferably, the latter hysteresis element 17 is arranged in a motor vehicle 30 due to the lower coefficient of friction for transmitting the thrust torque (transmission input shaft 9 to first side disc 22) and the hysteresis element 17 with the friction lining 25 is arranged in a motor vehicle 30 due to the higher coefficient of friction for transmitting the traction torque (first side disc 22 to transmission input shaft 9) (cf. Fig. 7 ). Independently of the above, the preloading means 12 of the torque limiter unit 11 is axially supported on the outer hub 10 by means of a retaining ring 14, and the counterbearing 13 is formed integrally with the outer hub 10.

[0058] In Fig. 3 is a schematic diagram of a torsional vibration damper 1 with a rotation axis 2 in section on a transmission input shaft 9 (shown in dashed lines). The torsional vibration damper 1 is similar to that in Fig. 1described, and in this respect, reference is made to the description therein. The torsional vibration damper 1 here also comprises a centrifugal pendulum-type absorber 19. The centrifugal pendulum-type absorber 19 is arranged radially outside the (in this case radially smaller) second side plate 23 and in radial partial overlap laterally (preferably on the engine side) of the first side plate 22.

[0059] In Fig. 4 is a circuit diagram of a torsional vibration damper 1, such as in Fig. 1shown. On the left in the image are the (engine-side) side plates 22, 23 of a multi-flange damper 4, which is connected by means of a friction element 34 to the adjacent first flange 5 and the second flange 6 (somewhat centrally in the image) for a desired hysteresis effect. The damper forms the torque-transmitting stop 50 on one side of each of these flanges 5, 6, preferably in the form of a spacer bolt, by which the two side plates 22, 23 are riveted together. In particular, two stops 50 are provided, which are spaced 180° apart from one another.

[0060] A central flange 7 is arranged between the two (hub) flanges 5, 6, which are each connected to the two adjacent flanges 5, 6 by means of a helical compression spring 20 and a friction element 34 in such a way that relative rotation is possible elastically and with friction up to a first clearance angle 39 with the first flange 5 and up to a second clearance angle 40 with the second flange 6. The first flange 5 and the second flange 6 are each connected to the outer hub 10 in a torque-transmitting manner. In a first direction of rotation (for example, the thrust direction), a first angle of rotation 41 between the outer hub 10 and the first flange 5 is freely movable, i.e., freely movable in the event of excitation. Likewise, in a second direction of rotation (for example, the tensile direction), a second angle of rotation 42 between the outer hub 10 and the second flange 6 is freely movable, i.e., freely movable in the event of excitation.In the respective opposite direction, an (angular) clearance 43 is provided. The outer hub 10, in turn, is connected (with a clearance 43 and a friction element 34, or frictionally) to the outer plates 33, and the inner hub 8 (on the transmission connection side) is connected to the inner plates 32 in a functionally similar manner. The outer plates 33 and the inner plates 32 form the functional unit of the torque limiter unit 11.

[0061] In Fig. 5 is a circuit diagram of a non-stressed torsional vibration damper 1, as it is largely in Fig. 4is shown. In this respect, reference is made to the previous description. However, a pre-damper 18 is additionally provided here, which is connected between the outer hub 10 and the (hub) flanges 5, 6 of the multi-flange damper 4, wherein the pre-damper output 44 forms the direct connection to the (hub) flanges 5, 6 and the outer hub 10 is connected to the multi-flange damper 4 in a torque-transmitting manner only indirectly via the pre-damper 18. The pre-damper 18, similar to the multi-flange damper 4, comprises an energy storage element, for example a helical compression spring 20, and a friction element 34, as well as a (third) clearance angle 45, around which the outer hub 10 and the pre-damper output 44 can be rotated relative to one another. The damping properties, however, are designed significantly differently, for example, softer and with a greater dissipation component.

[0062] In Fig. 6is a circuit diagram of a torsional vibration damper 1, as it is largely used in Fig. 5 is shown. In this respect, reference is made to the previous description. However, a pre-damper 18 is provided here, which is connected between the inner hub 8 and the inner plates 32, wherein the pre-damper output 44 forms the direct connection to the inner plates 32 and the inner hub 8 is only indirectly connected to the torque limiter unit 11 via the pre-damper 18 in a torque-transmitting manner. The pre-damper 18 is, for example, as shown in Fig. 5 described.

[0063] In the Figures 7a to 7c the torsional vibration damper 1 is made of Fig. 1 shown in section and in a plan view, with the torque flow in traction mode shown, in Fig. 7b at half the angle of rotation and in Fig. 7cat full angle of rotation. The two stops 50 are formed by spacer bolts, against which both flanges 5, 6 rest in the nominal position (relaxed). The torque is introduced clockwise via the two side plates 22, 23 (partially removed or cut free in the plan views). The spacer bolts are firmly connected to the side plates 22, 23, so that the torque is transferred from the spacer bolts to the first flange 5. The second flange 6 transfers the torque to the adjacent helical compression spring 20. This is compressed and transmits the torque to the center flange 7. The center flange 7 transfers the torque to the next helical compression spring 20. In the process, the center flange 7 is rotated by approximately half the angle of rotation of the second flange 6. This configuration thus forms a series connection of the two aforementioned compression springs 20.The latter compression spring 20 transmits torque to the first flange 5, which moves relative to the side discs 22, 23. The first flange 5 rests against the external toothing 31a after a clearance 43 greater than 0.0 mm and less than 0.5 mm has been overcome. The torque is then introduced into the torque limiter unit 11. The torque is distributed such that the first flange 5 resting against the torque limiter unit 11 transmits more torque than the second flange 6. As soon as the torque has reached a limit value, the teeth of both flanges 5, 6 rest against the external toothing 31a of the torque limiter unit 11, and two of the three flanges 5, 6, 7 transmit torque. In this direction of rotation, the external toothing 31a of the torque limiter unit 11 acts as a torque limiter.

[0064] In the Figures 8a to 8c the torsional vibration damper 1 is made of Fig. 1shown in section and in a plan view, with the torque flow in overrun mode shown, in Fig. 8b at half the angle of rotation and in Fig. 8c at full angle of rotation. In the opposite direction, the torque is transferred from the inner hub 8 via the torque limiter unit 11 to the external toothing 31a. Here, too, the clearance 43 between the external toothing 31a and the teeth of the flanges 5, 6 must first be overcome. In this direction of rotation, there is a relative movement of the second flange 6 to the two side plates 22, 23. The relative movement, together with the hysteresis element 17, generates additional friction on the side plates 22, 23. In this direction of rotation, the external toothing 31a of the torque limiter unit 11 acts as a torque transmitter.

[0065] In Fig. 9The clearance 43 between a tooth of the first flange 5 and the external toothing 31a is shown again in detail. The same applies to the second flange 6 on the other side of the torsional vibration damper 1.

[0066] In Fig. 101 schematically shows a (hybrid) drive train 3 in a (hybrid) motor vehicle 30. An electric drive motor 27 is connected via its drive shaft 24 (rotor shaft) and an internal combustion engine 46 are connected via its combustion shaft 47 in parallel to one another, transmitting torque to the left drive gear 28 and the right drive gear 29, which form the consumer. The motor vehicle 30 is optionally designed as a front-wheel drive vehicle, so that the electric drive motor 27 and the internal combustion engine 46 are arranged in front of the driver's cab 48. Furthermore, the electric drive motor 27 and the internal combustion engine 46 are optionally arranged transversely, i.e., with the rotor shaft 24 and combustion shaft 47 transverse to the longitudinal axis 49 of the motor vehicle 30.

[0067] The preceding embodiments relate to a torsional vibration damper 1 with a rotation axis 2 for a drive train 3, comprising at least the following components: a multi-flange damper 4 with a plurality of flanges 5, 6, 7 for the shear torque-dependent and tensile torque-dependent damping of torsional vibrations; a torque limiter unit 11, which is arranged radially inside the multi-flange damper 4 and has inner plates 32 and outer plates 33 for limiting a maximum transmittable torque; an outer hub 10, which is arranged radially inside the multi-flange damper 4 and radially outside the torque limiter unit 11 and which connects the multi-flange damper 4 to the torque limiter unit 11 in a torque-transmitting manner; and an inner hub 8, which is arranged radially inside the torque limiter unit 11 for connection to a transmission input shaft 9, wherein the outer hub 10 has an external toothing 31a which is in alternating engagement with the flanges 5, 6, 7 of the multi-flange damper 4 in a manner dependent on the thrust torque and the tensile torque, and wherein the outer hub 10 has an internal toothing 31b into which the outer plates 33 of the torque limiter unit 11 are suspended.

[0068] With the torsional vibration damper proposed here, the moment of inertia on the output side or gearbox side is particularly low. List of reference symbols

[0069] 1 Torsional vibration damper 31a external gearing 2 axis of rotation 31b Internal gearing 3 (Hybrid) powertrain 32 inner slats 4 Multi-flange damper 33 Outer slat 5 first flange 34 Friction element 6 second flange 35 Centering sleeve 7 center flange 36 first axial face 8 inner hub 37 second axial face 9 Transmission input shaft 38 Hysteresis preloading device 10 Outer hub 39 first clearance angle 11 Torque limiter unit 40 second clearance angle 12 Preloading device 41 first angle of rotation 13 Counter bearing 42 second twist angle 14 Retaining ring 43 Game 15 Inner shoulder of the outer hub 44 Pre-damper output 16 Outer shoulder of the outer hub 45 third clearance angle (pre-damper) 17 Hysteresis element 46 internal combustion engine 18 Pre-damper 47 combustion engine shaft 19 Centrifugal pendulum 48 Driver's cab 20 helical compression spring 49 Longitudinal axis 21 spring axle 50 stop 22 first side window 23 second side window 24 drive shaft 25 Friction lining 26 Centering element 27 electric drive machine 28 left drive wheel 29 right drive wheel 30 (Hybrid) motor vehicle

Claims

1. A torsional vibration damper (1) having an axis of rotation (2) for a drive train (3), having at least the following components: - a multi-flange damper (4) having a plurality of flanges (5, 6, 7) for the shear torque-dependent and tensile torque-dependent damping of torsional vibrations; - a torque limiter unit (11) arranged radially within the multi-flange damper (4) and having inner plates (32) and outer plates (33) for limiting a maximum transmittable torque; - an outer hub (10) arranged radially within the multi-flange damper (4) and radially outside the torque limiter unit (11) and which outer hub connects the multi-flange damper (4) to the torque limiter unit (11) in a torque-transmitting manner; and - an inner hub (8) arranged radially inside the torque limiter unit (11) for connection to a transmission input shaft (9), wherein the outer hub (10) has an internal toothing (31b), into which the outer plates (33) of the torque limiter unit (11) are suspended, characterized in that the outer hub (10) has an external toothing (31a) in alternating shear torque-dependent and tensile torque-dependent engagement with the flanges (5, 6, 7) of the multi-flange damper (4).

2. The torsional vibration damper (1) according to claim 1, wherein the torque limiter unit (11) has a pretensioning means (12) and a counter bearing (13), between which the inner plates (32) and outer plates (33) are arranged alternately in the axial direction for limiting the maximum transmittable torque between the inner hub (8) and the outer hub (10), and the pretensioning means (12) and the counter bearing (13) are supported axially on the outer hub (10).

3. The torsional vibration damper (1) according to claim 2, wherein the pretensioning means (12) and the counter bearing (13) are arranged radially within the outer hub (10).

4. The torsional vibration damper (1) according to claim 2 or 3, wherein the counter bearing (13) is formed integrally with the outer hub (10) and the pretensioning means (12) is axially supported within the outer hub (10) by means of a locking ring (14), or wherein the counter bearing (13) is formed by means of a locking ring (14) and the pretensioning means (12) is axially supported by means of an integral inner shoulder (15) of the outer hub (10).

5. The torsional vibration damper (1) according to any one of claims 1 to 4, wherein the multi-flange damper (4) has at least one stop (50), with which one of the flanges (5, 6, 7) can come into contact during the transmission of thrust torque, and with which another of the flanges (5, 6, 7) can come into contact during the transmission of tensile torque, wherein the contact of the respective flange (5, 6) with the stop (50) is free of play, while the simultaneous engagement of the respective flange (5, 6) with the outer hub (10) is subject to play.

6. The torsional vibration damper (1) according to any one of claims 1 to 5, wherein a pre-damper (18) is provided on the inner hub side and / or the outer hub side.

7. The torsional vibration damper (1) according to any one of claims 1 to 6, wherein at least three flanges (5, 6, 7) are connected in series with one another.

8. The torsional vibration damper (1) according to any one of claims 1 to 7, wherein at least one centrifugal pendulum (19) is further provided, wherein preferably at least one of the centrifugal pendulums (19) is fixed to an axially central flange (7) of at least three flanges (5, 6, 7).

9. The torsional vibration damper (1) according to any one of claims 1 to 8, wherein the multi-flange damper (4) comprises at least one helical compression spring (20) with a straight spring axis (21) between the plurality of flanges (5, 6, 7), wherein preferably the at least one helical compression spring (20) is guided radially only by at least one of the flanges (5, 6, 7).

10. The torsional vibration damper (1) according to any one of claims 1 to 9, wherein at least one side disc (22, 23) is provided for connection to a drive shaft (24), wherein the at least one side disc (22, 23) is connected on the connection side to the multi-flange damper (4) in a torque-transmitting manner, wherein the at least one side disc (22, 23) is preferably spaced from one or the helical compression spring (20) during operation of the torsional vibration damper (1).

11. The torsional vibration damper (1) according to claim 10, wherein at least one hysteresis element (17) is formed between the at least one side disc (22, 23) and one of the flanges (5, 6), wherein, preferably under axial hysteresis pretensioning, a first flange (5) is in frictional contact with a first side disc (22) by means of a friction lining (25) and a second flange (6) is in direct frictional contact with a second side disc (23).

12. The torsional vibration damper (1) according to any one of claims 1 to 11, wherein the multi-flange damper (4) comprises three or more axially adjacent flanges (5, 6, 7) and the at least one axially central flange (7) is centred on the outer hub (10) and is axially supported by two axially adjacent flanges (5, 6), preferably by means of a low-friction centring element (26).