Gear wheel with integrated torsional vibration damper

Abstract

The invention relates to a gear wheel (1) with an integrated torsional vibration damper (2), having a ring gear (3) which is mounted rotatably about an axis of rotation (D) and comprises at least one input flange portion (12) for receiving a torque; at least one output flange portion (13) for delivering a torque to a shaft; and a plurality of energy storage elements (10, 11) which are distributed in the circumferential direction (U) of the gear wheel (1) and are provided in the torque flow between the input flange portion (12) and the output flange portion (13) and which are biased against one another in pairs, wherein the output flange portion (13) has at least one ring segment-shaped cutout (15) which extends in the circumferential direction (U) and the ends (16) of which are delimited in the circumferential direction (U) by at least one radial web (18) of the output flange portion (13), one of the energy storage elements (10) is provided in one of the two ends (16) so as to contact the radial web (18) in order to be compressed clockwise, and another energy storage element of the energy storage elements (11) is provided in the other end of the two ends (16) so as to contact the radial web (18) or another radial web (19) in order to be compressed counterclockwise.

Description

[0001] Gear with integrated torsional vibration damper

[0002] The present invention relates to a gear with an integrated torsional vibration damper, for example for a gearbox in a drive train of a motor vehicle.

[0003] Periodic or impulsive torque zero crossings in internal combustion engines, combined with play in the drivetrain (e.g., in shaft connections or gears), can lead to disturbing noises such as rattling or knocking. Torsional vibration dampers with specific stiffness and friction characteristics are used to reduce these noises.

[0004] These noise phenomena pose a particular challenge in hybrid or fully electric powertrains. For example, the combustion engine produces periodic noises (rattling) when electric motors (generator or traction motor) that are not coupled without backlash or via gear stages are operated without load or at low load.

[0005] In the case of an unfired or mechanically decoupled combustion engine in conjunction with an electric drive or in the case of a fully electric drive - such as an electrically driven axle - even single zero torque crossings of the electric drive motor (load change) can lead to clicking or knocking noises.

[0006] In this context, for example, a gear with an integrated torsional vibration damper is known from DE 10 2013 221 361 A1.

[0007] The object of the present invention is to provide a gear by which torsional vibrations can be effectively reduced, in particular to prevent disturbing noises during the operation of a motor vehicle.According to the invention, this problem is solved by a gear with an integrated torsional vibration damper according to claim 1, comprising a gear ring rotatably arranged about an axis of rotation with at least one input flange section for receiving a torque, at least one output flange section for transmitting a torque to a shaft, and several energy storage elements arranged in pairs and preloaded against each other in the circumferential direction of the gear and in the torque flow between the input flange section and the output flange section, wherein the output flange section has at least one circumferentially extending, ring segment-shaped recess, the ends of which are limited in the circumferential direction by at least one radial web of the output flange section.

[0008] Since one of the energy storage elements is arranged in one of the two ends touching the radial web in order to be compressed clockwise, and since another of the energy storage elements is arranged in the other of the two ends touching the radial web or another radial web in order to be compressed counterclockwise, torsional vibrations can be effectively reduced.

[0009] In a neutral position of the torsional vibration damper integrated into the gear, the torque effects of the preloaded energy storage elements cancel each other out. When the input flange section and output flange section rotate relative to each other, the energy storage elements located in the direction of rotation are tensioned, while those located further back are relaxed. The preloaded state of all energy storage elements in a neutral position, combined with the continuous increase or decrease in torque of the energy storage elements located in the direction of rotation and those located further back during rotation, generates a torsional characteristic curve that is free of any torque jumps or a free angle in the region of the zero crossing.

[0010] The torque required for relative rotation is proportional to the angle of rotation and the stiffness of all energy storage elements, as well as to the radius on which they are arranged. The relaxing rear energy storage elements contribute to the required torque because their preload torque acting in the direction of rotation decreases during rotation, and the difference must therefore be additionally applied.

[0011] The spring travel and the preload travel of the energy storage elements are preferably selected such that, in a maximally twisted position, the energy storage elements located in the direction of rotation do not prematurely reach their limit, and that the energy storage elements at the rear do not experience complete unloading.

[0012] It is advantageous if the input flange section has at least one annular segment-shaped projection extending axially along the gear and into the annular segment-shaped recess of the output flange section, wherein one of the energy storage elements is arranged between an edge surface of the radial rib and an adjacent end of the annular segment-shaped projection, and wherein the other energy storage element is arranged between another edge surface of the radial rib or the further radial rib and an adjacent, further end of the annular segment-shaped projection. This effectively reduces torsional vibrations.

[0013] Alternatively, it is advantageous if the input flange section has at least one circumferentially extending, annular segment-shaped recess, wherein one of the energy storage elements is arranged between an edge surface of the radial web and an adjacent edge of the annular segment-shaped recess of the input flange section, and wherein the other energy storage element is arranged between another edge surface of the radial web or the further radial web and an adjacent, further adjacent edge of the annular segment-shaped recess of the input flange section. This effectively reduces torsional vibrations while simultaneously simplifying the manufacturability of the gear. Preferably, a hub is formed in the radial direction of the gear within the output flange section, thereby improving the connection of the gear to other components.

[0014] Furthermore, preferably the output flange section is formed in one piece with the hub, which further improves the connection of the gear to other components.

[0015] Furthermore, it is advantageous if a splined connection is formed within the hub, which further improves the connection of the gear to other components.

[0016] It is also advantageous if the gear ring has two input flange sections that are axially spaced apart, and between which the radial web or circumferentially distributed radial webs are arranged. This effectively reduces torsional vibrations.

[0017] It is advantageous if the output flange section has at least one axial projection that engages, with limited circumferential rotation, in a corresponding stop recess of the input flange section to limit relative rotation of the torsional vibration damper clockwise and / or counterclockwise before the energy storage elements reach their limit. This effectively reduces torsional vibrations while simultaneously improving the durability of the gear.

[0018] Preferably, at least one friction device is arranged between the input flange section and the output flange section, thereby effectively reducing torsional vibrations. Equally preferably, the input flange section is rotatably supported on the output flange section via a rolling bearing. This effectively reduces torsional vibrations while simultaneously improving the durability of the gear.

[0019] The present invention is explained in more detail below with reference to preferred embodiments in conjunction with the accompanying figures. These show:

[0020] Figure 1: A first embodiment of a gear with a torsional vibration damper in a top view,

[0021] Figure 2: the gear from Figure 1 in a sectional view along the section line

[0022] AA,

[0023] Figure 3: the gear from Figure 1 in a sectional view along the section line

[0024] BB,

[0025] Figure 4: a second embodiment of a gear with a torsional vibration damper and a friction device in a half sectional view, and

[0026] Figure 5: a third embodiment of a gear with a torsional vibration damper in a half sectional view.

[0027] The following description relates to various embodiments of a gear 1 with an integrated torsional vibration damper 2. Features that are not characterized as essential to the invention in the following description are to be understood as optional.

[0028] Figures 1 to 3 show a first embodiment of a gear 1 with an integrated torsional vibration damper 2. The gear 1 has a toothed ring 3 which is rotatably arranged about an axis of rotation D. In the illustrated embodiment, the toothed ring has helical teeth, but could also, for example, have spur teeth.

[0029] The gear ring 3 is rotationally fixed to at least one input flange section 12 of the torsional vibration damper 2 for absorbing a torque, for example by welding. The input flange section 12 is essentially ring-shaped and arranged radially R of the gear 1 within the gear ring. The input flange section 12 can be formed integrally with the gear ring 3, but can also be formed as a separate component, as shown in Figures 1 to 3.

[0030] In particular, the gear ring 3 has two input flange sections 12 on its inner radial direction R, which are spaced apart from each other in the axial direction A of the gear 1 and which define the interior of the gear 1. It is possible that one of the two input flange sections 12 is formed integrally with the gear ring 3, and the other of the two input flange sections 12 is formed as a separate component, or that both input flange sections 12 are formed as separate components.

[0031] The torsional vibration damper 2 integrated into the gear 1 further comprises at least one output flange section 13 for transmitting a torque to a shaft (not shown). In the illustrated embodiment, a hub 4 is formed radially R within the output flange section 13, which defines the interior of the gear 1. A splined connection 5 is formed within the hub 4 for the rotationally fixed attachment of the shaft (not shown).

[0032] Although not shown, it is also possible to connect the output flange section 13 to a separate hub 4, for example by welding or riveting. It is also possible for the hub 4 not to have a splined connection 5, but instead to be shrink-fitted onto a shaft in a rotationally fixed manner, for example. In the illustrated embodiment, a single output flange section 13 is arranged centrally in the axial direction A between the two input flange sections 12. The output flange section 13 is formed integrally with the hub 4 and the splined connection 5 contained therein, for example in the form of a sintered component or a forged component.

[0033] The inlet flange sections 12 are rotatably supported on the outlet flange section 13 and on the hub 4, respectively, by means of rolling bearings 9, which are preferably designed as cage-guided ball bearings. More precisely, with reference to Figures 2 and 3, the left inlet flange section 12 is rotatably supported in a transition area between the central outlet flange section 13 and the hub 4 via the left rolling bearing 9, while the right inlet flange section 12 is rotatably supported in a transition area between the central outlet flange section 13 and the hub 4 via the right rolling bearing 9.

[0034] Furthermore, the torsional vibration damper 2 integrated into the gear 1 has several energy storage elements 10, 11 arranged in pairs and preloaded against each other in the circumferential direction U of the gear 1. The energy storage elements 10, 11 are arranged in the torque flow between the input flange section 12 and the output flange section 13. The energy storage elements 10, 11 are preferably designed as compressible helical springs.

[0035] In a neutral position of the torsional vibration damper 2 integrated into the gear 1, the torque effects of the preloaded energy storage elements 10, 11 cancel each other out. When the input flange section 12 and the output flange section 13 rotate relative to each other, the energy storage elements 10 located in the direction of rotation are tensioned, and the energy storage elements 11 located further back are relaxed. The preloaded state of all energy storage elements 10, 11 in a neutral position, as well as the continuous increase or decrease in torque of the energy storage elements 11, 10 located in the direction of rotation and those located further back, respectively, during rotation, generates a torsional characteristic curve that is free of any torque jumps or a free angle in the region of the zero crossing.

[0036] The output flange section 13 has at least one annular segment-shaped recess 15 extending in the circumferential direction U. The two ends 16 of the annular segment-shaped recess 15 are bounded in the circumferential direction U by at least one radial web 18 of the output flange section 13.

[0037] Specifically, in the case of a single ring-segment-shaped recess 15, only a single radial web 18 is provided, one edge surface 22 of which in the circumferential direction U defines one end 16 of the ring-segment-shaped recess 15 and the other edge surface 22 of which is opposite in the circumferential direction U defines the other end 16 of the ring-segment-shaped recess 15.

[0038] In this case, the torsional vibration damper 2 has only a single energy storage element 10, which is arranged in one of the two ends 16 of the annular segment-shaped recess 15, contacting the radial web 18, in order to be compressed clockwise to dampen the torsional vibration. The torsional vibration damper 2 also has only a single further energy storage element 11 in this case, which is arranged in the other of the two ends 16 of the annular segment-shaped recess 15, contacting the radial web 18, in order to be compressed counterclockwise to dampen the torsional vibration.

[0039] In the illustrated embodiment, the output flange section 13 has two annular segment-shaped recesses 15, each spaced apart in the circumferential direction U by a radial web 18, 19. Thus, there are a total of two radial webs 18, 19. The edge surface 22 of one radial web 18 defines one end 16 of the annular segment-shaped recess 15 in the circumferential direction U. The edge surface 22 of the other radial web 19, opposite in the circumferential direction U, defines the other end 16 of this annular segment-shaped recess 15. The same applies equally to the other annular segment-shaped recess 15. In this case, the torsional vibration damper 2 has two energy storage elements 10, each of which is arranged in one of the two ends 16 of the ring segment-shaped recesses 15 in contact with the respective radial web 18, 19 in order to be compressed clockwise to dampen the torsional vibration.In this case, the torsional vibration damper 2 also has two further energy storage elements 11, which are each arranged in the other of the two ends 16 of the ring segment-shaped recesses 15 in contact with the respective radial web 19, 18 in order to be compressed counterclockwise to dampen the torsional vibration.

[0040] More than two ring-segment-shaped recesses 15 can also be arranged in the output flange section 13. Regarding the ring-segment-shaped recesses 15, it should be noted that these recesses are completely surrounded by the output flange section 13 in the radial direction R and in the circumferential direction U, i.e., they have a closed contour. The corresponding edges of the radial webs 18, 19 and the edge surfaces 22, extending in the radial direction R, are part of this closed contour.

[0041] Accordingly, the inlet flange section 12, or each of the inlet sections 12, has at least one annular segment-shaped projection 17 extending in the axial direction A, which extends into the respective annular segment-shaped recess 15 of the outlet flange section 13. The number of annular segment-shaped projections 17 per inlet flange section 12 corresponds to the number of annular segment-shaped recesses 15 in the outlet flange section 13.

[0042] One of the energy storage elements 10 is arranged circumferentially U between the edge surface 22 of one radial web 18 and an adjacent end 20 of the annular segment-shaped projection 17 of the inlet flange section 12. The other energy storage element 11 is arranged circumferentially U between another edge surface 22 of the radial web 18 (in the case of a single annular segment-shaped recess 15 in the outlet flange section 13) or of the further radial web 19 (in the case of two or more annular segment-shaped recesses 15 in the outlet flange section 13) and an adjacent, further end 21 of the annular segment-shaped projection 17 of the inlet flange section 12.

[0043] Furthermore, the output flange section 13 has at least one axial projection 23 which engages, with limited rotation in the circumferential direction U, in a corresponding stop recess 24 of the input flange section 12 in order to limit relative rotation of the torsional vibration damper 2 clockwise and / or counterclockwise before the energy storage elements 10, 11 engage. The axial projection(s) 23 can extend only in the direction of one of the input flange sections 12 and engage in one or the stop recesses 24, or extend in the direction of both input flange sections 12 and engage in one or the stop recesses 24 of both input flange sections 12. In the illustrated embodiment, two axial projections 23 and two stop recesses 24 are provided on each side.

[0044] Figure 4 shows a second embodiment of a gear 1 with an integrated torsional vibration damper 2. Only the differences from the first embodiment are discussed, with identical reference numerals denoting identical features.

[0045] In comparison to the first embodiment, the gear 1 shown in Figure 4 additionally features a friction device 6, which is integrated into the torsional vibration damper 2. In the axial direction A on both sides of the gear 1, between the input flange section 12 and the output flange section 13, preferably in an annular recess, a friction element 7 and a disc spring 8 acting on this element in the axial direction A are provided. The friction device 6 can generate hysteresis during the damping of the torsional vibrations or during the relative rotation of the input flange section 12 to the output flange section 13.

[0046] Figure 5 shows a third embodiment of a gear 1 with an integrated torsional vibration damper 2. Only the differences from the first and second embodiments are discussed, with identical reference numerals denoting identical features.

[0047] Instead of ring-segment-shaped projections 17, the input flange section 12 of the gear 1 according to the third embodiment has at least one ring-segment-shaped recess 14 extending in the circumferential direction U. More precisely, a ring-segment-shaped recess 14 is provided in each of the input flange sections 12 for each energy storage element 10.

[0048] In the circumferential direction U, one of the energy storage elements 10 is arranged between an edge surface 22 of the radial web 18 and an adjacent edge of the annular segment-shaped recess 14 of the inlet flange section 12. In the circumferential direction U, the other of the energy storage elements 11 is arranged between another edge surface 22 of the radial web 18 or of the further radial web 19 and an adjacent, further adjacent edge of the annular segment-shaped recess 14 of the inlet flange section 12.

[0049] It is evident that the diameter of the energy storage elements 10 must be larger than in the first and second embodiments so that the ends of the energy storage elements 10 can abut the edges of the annular segment-shaped recesses 14 of the inlet flange sections 12. Accordingly, the annular segment-shaped recesses 15 of the outlet flange section 13 must also have a greater radial extent R compared to the first and second embodiments in order to accommodate the corresponding energy storage elements 10.

[0050] Although not shown, the third embodiment may also include the friction device 6 shown in the second embodiment.

[0051] The preceding embodiments relate to a gear 1 with an integrated torsional vibration damper 2, comprising a toothed ring 3 rotatably arranged about an axis of rotation D, with at least one input flange section 12 for receiving a torque, at least one output flange section 13 for transmitting a torque to a shaft, and several energy storage elements 10, 11 arranged in pairs and preloaded against each other in the torque flow between the input flange section 12 and the output flange section 13, wherein the output flange section 13 has at least one annular segment-shaped recess 15 extending in the circumferential direction U, the ends 16 of which are bounded in the circumferential direction U by at least one radial web 18 of the output flange section 13, wherein one of the energy storage elements 10 is arranged in one of the two ends 16 contacting the radial web 18.to be compressed clockwise, and wherein in the other of the two ends 16 another of the energy storage elements 11 is arranged touching the radial web 18 or another radial web 19, to be compressed counterclockwise.

[0052] List of reference signs

[0053] 1 gear

[0054] 2 torsional vibration dampers

[0055] 3 sprocket

[0056] 4 hub

[0057] 5 Splined connection

[0058] 6 Friction device

[0059] 7 friction ring

[0060] 8 Belleville washers

[0061] 9 rolling bearings

[0062] 10 Energy storage element

[0063] 11 additional energy storage element

[0064] 12 Inlet flange section

[0065] 13 Outlet flange section

[0066] 14 ring-segment-shaped recess of the inlet flange section

[0067] 15 ring-segment-shaped recess of the output flange section

[0068] 16 End of the ring segment-shaped recess of the output flange section

[0069] 17 ring-segment-shaped projection of the inlet flange section

[0070] 18 radial web

[0071] 19 additional radial webs

[0072] 20 End of the ring-segment-shaped projection of the inlet flange section

[0073] 21 further end of the ring segment-shaped projection of the inlet flange section

[0074] 22 Edge area

[0075] 23 Axial projection

[0076] 24 Stop recess

[0077] A axial direction

[0078] D axis of rotation

[0079] R radial direction

[0080] U circumferential direction

Claims

Patent claims 1. Gear (1) with integrated torsional vibration damper (2), comprising a toothed ring (3) rotatably arranged about an axis of rotation (D), with at least one input flange section (12) for receiving a torque, at least one output flange section (13) for transmitting a torque to a shaft, and several energy storage elements (10, 11) arranged in pairs and preloaded against each other in the torque flow between the input flange section (12) and the output flange section (13), wherein the output flange section (13) has at least one annular segment-shaped recess (15) extending in the circumferential direction (U), the ends (16) of which are bounded in the circumferential direction (U) by at least one radial web (18) of the output flange section (13), wherein a [missing element] is in contact with the radial web (18) at one of the two ends (16). the energy storage elements (10) are arranged to be compressed clockwise,and wherein in the other of the two ends (16) a further energy storage element (11) is arranged touching the radial web (18) or another radial web (19) in order to be compressed counterclockwise.

2. Gear (1) according to claim 1, wherein the input flange section (12) has at least one annular segment-shaped projection (17) extending in the axial direction (A) of the gear (1) and extending into the annular segment-shaped recess (15) of the output flange section (13), wherein one of the energy storage elements (10) is arranged between an edge surface (22) of the radial web (18) and an adjacent end (20) of the annular segment-shaped projection (17), and wherein the other of the energy storage elements (11) is arranged between another edge surface (22) of the radial web (18) or the further radial web (19) and an adjacent further end (21) of the annular segment-shaped projection (17).

3. Gear (1) according to claim 1, wherein the input flange section (12) has at least one circumferentially extending, ring segment-shaped recess (U). (14) having one of the energy storage elements (10) arranged between an edge surface (22) of the radial web (18) and an adjacent edge of the ring segment-shaped recess (14) of the inlet flange section (12), and the other of the energy storage elements (11) arranged between another edge surface (22) of the radial web (18) or the further radial web (19) and an adjacent, further adjacent edge of the ring segment-shaped recess (14) of the inlet flange section (12).

4. Gear (1 ) according to one of claims 1 to 3, wherein a hub (4) is formed in the radial direction (R) of the gear (1 ) within the output flange section (13).

5. Gear (1 ) according to claim 4, wherein the output flange section (13) is formed integrally with the hub (4).

6. Gear (1 ) according to claim 4 or 5, wherein a splined connection (5) is formed within the hub (4).

7. Gear (1 ) according to one of claims 1 to 6, wherein the gear ring (3) has two input flange sections (12) which are spaced apart from each other in the axial direction (A) and between which the radial web (18) or the radial webs (18, 19) distributed in the circumferential direction (U) are arranged.

8. Gear (1 ) according to one of claims 1 to 7, wherein the output flange section (13) has at least one axial projection (23) which engages in a circumferentially limited rotational direction (U) into a corresponding stop recess (24) of the input flange section (12) in order to limit a relative rotation of the torsional vibration damper (2) clockwise and / or counterclockwise before the energy storage elements (10, 11 ) engage. - 16 - 9. Gear (1 ) according to one of claims 1 to 8, wherein at least one friction device (6) is arranged between the input flange section (12) and the output flange section (13).

10. Gear (1 ) according to one of claims 1 to 9, wherein the input flange section (12) is rotatably supported on the output flange section (13) via a rolling bearing (9).

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