CN115370709A

CN115370709A - Torsional vibration damper with disk spring diaphragm

Info

Publication number: CN115370709A
Application number: CN202210450582.8A
Authority: CN
Inventors: 马蒂厄·埃克
Original assignee: Schaeffler Technologies AG and Co KG
Current assignee: Schaeffler Technologies AG and Co KG
Priority date: 2021-05-21
Filing date: 2022-04-27
Publication date: 2022-11-22
Also published as: DE102021113248A1

Abstract

The invention relates to a torsional vibration damper, in particular a dual mass flywheel (1), having an input part (2) and an output part (3) which can be rotated relative to one another against the action of a curved spring arrangement (4), wherein the curved spring arrangement (4) is supported on the one hand at the input part (2) and on the other hand at a flange (6) which is connected to the output part (3), wherein a sealing diaphragm which is designed as a disk spring diaphragm (7) is arranged at the output part (3) or the input part (2) and is in contact with the other part (2 or 3). For improved noise reduction, a disk spring (17) is additionally provided between the input part (2) and the output part (3).

Description

Torsional vibration damper with disk spring diaphragm

Technical Field

The invention relates to a torsional vibration damper, in particular a dual mass flywheel, having an input part and an output part which can be rotated relative to one another against the action of arcuate spring devices, wherein the arcuate spring devices are supported on the one hand at the input part and on the other hand at a flange which is connected to the output part, wherein a sealing diaphragm which is designed as a disk spring diaphragm is arranged at the output part or the input part and is in contact with the other part.

Background

Such torsional vibration dampers or dual mass flywheels are used as vibration dampers for torsional vibrations in the drive train of a motor vehicle, wherein the torsional vibration dampers are usually arranged between the crankshaft of an internal combustion engine driving the motor vehicle and a vehicle clutch mounted upstream of the transmission. Torsional oscillations caused by the irregular drive torque of an internal combustion engine, which is usually designed as a piston engine, are damped by the primary and secondary masses being rotatable relative to one another against spring forces and optionally also against dry friction. Such a vibration damper can also additionally contain one or more centrifugal pendulum devices, which again improve the action.

The disk spring or sealing diaphragm described above serves to seal the curved spring arrangement from the environment and to prevent dirt (dust or abrasive particles) or (sprayed) water from entering. Such sealing diaphragms are typically in sliding contact with a friction or diaphragm ring provided on the mating member. The sealing diaphragm is prestressed in the axial direction in such a way that its contact surface presses against the friction ring. The sealing diaphragm forms a seal together with the friction ring in order to seal the space in which the arcuate spring arrangement is located from the spray water, dust or other harmful substances, which may flush away grease required for lubrication from said space. The sealing diaphragm therefore rests with its designed and defined force on the opposing plastic friction ring. This ensures a specific friction coefficient and at the same time prevents rattling due to steel and steel friction.

In dual mass flywheels and dampers, the installation space is often strongly influenced by the installation of the surrounding components. Sometimes, only a very small radial structural space is available. The sealing membrane should however still meet the sealing requirements and have a preset minimum basic hysteresis (required moment in Nm, depicted as positive and negative with respect to the rotation angle). In the case of small radial installation spaces, it is often difficult to position sufficient lever arms of the sealing diaphragm in the installation space, which lever arms exert sufficient force on the opposing friction ring in order to achieve the desired basic hysteresis. However, this substantial hysteresis is necessary in today's smaller engines, usually three-cylinder engines, in order to achieve the desired starting behavior.

A torsional vibration damper, in particular a dual mass flywheel having an input part and an output part which can be rotated relative to one another against the action of arcuate spring devices which are supported on the one hand at the input part and on the other hand at a flange which is connected to the output part, is known from DE 10 2019 101 A1. For improved vibration isolation, a centrifugal pendulum device is additionally provided on the input part. There, a disk spring can also be provided between the flange and the cover of the input part.

DE 10 2018 125 406 A1 discloses a torsional vibration damper, in particular a dual mass flywheel, having an input part and an output part which are rotatable relative to one another against the action of arcuate spring means, wherein the arcuate spring means are supported on the one hand at the input part and on the other hand at a flange which is connected to the output part, wherein a sealing diaphragm which is designed as a disk spring diaphragm is arranged at the output part and is in contact with a cover of the input part via a friction ring. The sealing membrane seals the interior space from dirt and moisture. Which apparatus forms the preamble of claim 1.

Modern vehicles use increasingly lighter engines and lower rotational speeds, and therefore generate less operating noise, so that the driver now hears what was previously not even audible in the context of an operating engine, such as engine spurs, tooth rattle in the transmission, other noise of the transmission or double clutches, or tooth play of the driven hub and transmission input shaft. Starting and stopping facilities are increasingly used for internal combustion engines to reduce fuel consumption causing other undesirable noises when starting and stopping the engine. On start-up, for example, a starter is engaged. When stopped, the shock of the flange and the spring occurs in the vibration damper. In vehicles with centrifugal pendulum devices, the pendulum mass slips out of its equilibrium position at a defined rotational speed when the engine is stopped and an audible impact of the pendulum mass or of the rolling element at the flange element occurs.

Disclosure of Invention

The object of the present invention is therefore to design a torsional vibration damper such that it is improved with respect to the prior art with respect to undesirable noise, yet can be produced in a simple and cost-effective manner and also maintains a saving in installation space.

This object is achieved by a torsional vibration damper according to the invention. Preferred embodiments of the invention are given in the following description, which may each show aspects of the invention individually or in combination.

The invention therefore proposes a torsional vibration damper, in particular a dual mass flywheel, having an input part and an output part which can be rotated relative to one another against the action of an arcuate spring arrangement, wherein the arcuate spring arrangement is supported on the one hand at the input part and on the other hand at a flange which is connected to the output part, wherein a sealing diaphragm which is designed as a disk spring diaphragm is arranged at the output part or at the input part and is in contact with the other part, wherein additionally a disk spring is arranged between the input part and the output part.

By using the additional disk spring according to the invention in addition to the disk spring diaphragm, the construction expenditure and the space requirement are not significantly increased, but a pronounced noise avoidance and a sound insulation of the rattling or rattling components is achieved.

Just during the start-up and shut-down operation of the internal combustion engine, the driver is thus kept away from undesirable noises. The driving comfort is improved by quieter running. A slight increase in the friction between the input part and the output part by the disk spring is a compromise for increasing the sound damping effect, since sound damping is currently of particular importance to car manufacturers.

The disk spring according to the invention has, in addition to the disk spring diaphragm, further advantages: the more sensitive disk spring diaphragm is protected and fixed during assembly, since the stronger disk spring, and possibly the plastic ring, comes into contact with the cover of the input part for the first time during installation in the vehicle and the disk spring diaphragm is therefore not able to deform plastically. Thus avoiding permanent deformation. The entire damper thus becomes stronger.

The disk spring diaphragm can be fixed on the input part and slide on the output part directly or via a diaphragm ring in order to close and protect the space in which the arc-shaped spring arrangement is located. Likewise, the belleville spring diaphragm may be fixed on the output and slide at the input directly or via a diaphragm ring. The same protective effect also occurs. In one embodiment, the input portion has a cover that surrounds or covers the arcuate spring space. The disk spring diaphragm can then be arranged between the cover and the output or the flange of the output. In this case, the disk spring diaphragm can also be fixed to the cover and can slide on the flange or it can be fixed to the flange and can slide on the cover. In both cases, it again acts directly or via a sliding ring or diaphragm ring.

The additional disk spring according to the invention, which is located between the input part and the output part, can be simply inserted and held by its own stress, or is fixed at one of the two parts and slides at the other part. In a preferred embodiment, the disk spring can be fastened to the flange or another element of the output part, such as, for example, a hub, which is preferably toothed and bears with its radial and axial outer side or its outer edge slidingly against the cover of the input part. The disk spring in this embodiment, in its shape, does not correspond precisely to a disk which runs flat on the inside and projects upward at the edge, but rather to a disk which has no inner part, is composed only of the disk edge, or in other words to a disk which has no "bottom" and has a hole in the middle. The inner edge of the disk spring edge is then clamped directly or indirectly in a positive or non-positive manner on the flange or hub, and the outer edge slides frictionally on the mating piece, in this case the cover of the input part. The input part and the output part are preferably mounted close to each other so that the disk spring is tensioned or easily deformed so that an additional axial force occurs between the input part and the output part. The additional force increases the friction and the basic hysteresis (Grundhysterese) of the device and seals the curved spring space better against acoustic radiation or water and dirt.

The belleville springs are preferably further inboard, i.e. radially closer to the axis of rotation, than the belleville spring diaphragms. The disk spring is located, for example, in the vicinity of the rivet, i.e. radially slightly beyond the rivet on the flange side. The radially outward force edge of the disk spring offers the advantage of an increased friction moment compared to a smaller friction edge if the disk spring extends in the direction of the inner diameter.

In a preferred embodiment, a second belleville spring is provided between the input and output portions. This achieves a rise in friction and a further increase in the basic hysteresis of the entire device. In summary, three abutting force-generating elements then act between the input part and the output part. During operation, then, upon a mutual movement of the input part and the output part about a common axis of rotation, the three friction elements act, as a result of which again the desired isolation from noise or dirt can be set and adjusted better.

The disk spring may be made of any suitable material having sufficient elasticity or spring action. The edge of the disk spring must be slidingly and frictionally placed on the mating piece, which is still rotationally movable relative to the mating piece. Therefore, the disk spring must elastically compensate for the unevenness (uebenheiten) or incorrect alignment of the (ausfedern) rotational axis and then return again into its original shape. The disk spring can be made of metal or plastic (fiber reinforced material). Preferably, the disk spring is however made of spring steel, a material which is very suitable for elastic deformation and restoring deformation.

One or both disc springs can be fixed directly at the member carrying them, the input or the output. This can be done via plugging or clamping. However, variants are preferred in which one or both disk springs are fixed by means of one, two or more rings at the component carrying them. The ring carrying the load can thus be fixed at the primary part or at the secondary part. The one or more rings are preferably made of plastic. This has the advantage that the coefficient of friction of the material is small and known. The plastic ring or rings then hold the disk spring(s) at their inner side at their associated component in such a way that: it is pressed or snapped on, for example, while the outer side or outer edge of the disk spring slides elastically against the opposing component and its friction force is transmitted to the other component, thereby closing the curved spring space, however, acoustically.

One or both disk springs can slide with their outer edges directly on the metal counterpart. However, it is also possible to provide one or two friction rings, which result in a defined coefficient of friction. Here, it is also possible to use plastics having their known properties, such as low and defined friction.

A torsional vibration damper provided with an additional disk spring according to the invention can be "conventional" in the sense that it damps torsional vibrations only via the spring force, i.e. without any additional pendulum spring arrangement. In a preferred embodiment, the torsional vibration damper, however, additionally comprises one or more centrifugal pendulum devices, wherein in the case of two centrifugal pendulum devices, one can be arranged on the input part and the second on the output part. Such a torsional vibration damper is better in terms of damping than conventional torsional vibration dampers without a spring pendulum and is particularly suitable for engines with low rotational speeds or with start/stop automation. One or both disk springs then suppress the transmission of the rattling noise of the pendulum mass when it is at rest or when it comes to rest against its guide during operation.

The surface roughness and the material pairing of the disk spring can preferably be designed such that a desired coefficient of friction and the basic hysteresis associated therewith are achieved.

Drawings

The invention is explained in detail below with reference to the drawing according to two preferred embodiments, wherein the features shown below can each show aspects of the invention individually and in combination. The figures show:

FIG. 1 shows a dual mass flywheel according to the present invention, and

fig. 2 shows another dual mass flywheel according to the invention.

Detailed Description

Fig. 1 shows a cross-sectional view of a dual mass flywheel 1 according to the invention. Such a dual mass flywheel 1 is used, for example, in a drive train of a motor vehicle between a crankshaft of an internal combustion engine and a vehicle clutch. The axis of rotation of the dual mass flywheel 1 is denoted by R. The rotational axis is simultaneously the rotational axis of a crankshaft of an internal combustion engine (not shown, on the left in fig. 1) and the rotational axis of a vehicle clutch (not shown, on the right in fig. 1) arranged downstream. The dual mass flywheel 1 comprises a primary mass, referred to herein as the input part 2, and a secondary mass, referred to herein as the output part 3, which are rotatable relative to each other about an axis of rotation R against the force of an arcuate spring arrangement 4. The input part 2 comprises a primary flywheel 9 with an outer ring gear 10 and an inner cover disk 12, in the vicinity of which there is a sealed axial ring 11. The input part 2 also comprises a (primary mass) cover 5 on the clutch side, which encloses the arcuate spring arrangement 4 and the sliding sleeve 13.

The secondary mass 3 comprises a secondary flange 6 which is fixed via rivets 14 and whose flange limbs extend radially outward and bear against the spring ends of the arcuate spring devices 4. Radially inside, at the output 3, there is a toothed hub 15, which transmits the further transmitted rotational movement to a clutch or transmission. In order to seal the space accommodating the arcuate spring arrangement 4, on the secondary mass side, a disk spring diaphragm 7 is fixed radially on the inside at a flange 6 and rivets 14, extends radially outward and axially to the right in the direction of the clutch and interacts slidingly on the primary mass side with a diaphragm ring 8, a sliding ring, which is fixed on the inside of the cover 5.

In this embodiment, the belleville springs are now fixed at the output portion 3. Said disk spring is fixed by its inner side at the plastic ring 18 and/or at the hub 15, projects radially outward (i.e. upward in fig. 1) and axially toward the clutch (i.e. to the right in fig. 1) and slides by its outer side or its outer edge at the inner side of the cover 5 of the input part 2. After installation, the disk spring 17 is tensioned between the input part 2 and the output part 3, being pressed together slightly in the axial direction, so that an additional axial force is generated between the two components 2 and 3 via its stiffness or restoring force. Plate thickness and pitch control force characteristics of belleville springs 17. Thus, the disc spring 17 increases the basic hysteresis of the dual mass flywheel 1. At the same time, the disk spring 17 again limits the curved spring installation space in order to help trap dirt and water and prevent disruptive noises from leaving the curved spring installation space.

In this embodiment, the output part 3 furthermore contains a centrifugal pendulum device 16 which is fixed at the flange 6 and moves with it about the axis of rotation R relative to the input part 2. The centrifugal pendulum device serves to further damp torsional vibrations and has a pendulum mass which is movable between stops and can be moved back and forth in order to absorb energy and to again output energy. The rattling sound of the pendulum mass at its stop when the engine is stopped can thus just be damped by the disk spring 17.

In driving operation, the input part 2, which is now driven by the engine, and the output part 3, which is connected to the clutch or transmission, rotate about the axis of rotation R. In this case, the input part 3 and the output part 2 are now rotated relative to one another approximately about the axis of rotation R so that torsional vibrations or rotational irregularities of the crankshaft introduced into the input part 2 by the internal combustion engine are damped by the action of the bow spring arrangement 4 and of the centrifugal pendulum arrangement 16, so that the transmission input shaft driven by the hub 15 rotates more uniformly. The disk spring diaphragm 7 slides on the diaphragm ring 8 on the inside of the cover 5 and seals the arc-shaped spring space together with the axial ring 11. The outer edge of the disk spring 17 slides on the inside of the cover 5 and generates an axial force, which is derived from the rigidity of the disk spring 17 and its pretension. This increases the friction between the input portion 2 and the output portion 3 and thus increases the fundamental hysteresis of the overall apparatus.

Fig. 2 shows a further dual mass flywheel 1 according to the invention, wherein most components have already been described in relation to fig. 1. In this embodiment, the difference is that the cover 5 of the input part 2 is slightly larger and extends further downward (i.e. downward in fig. 2) toward the axis of rotation R, and an additional second disk spring 19 is provided radially inside the fastening ring of the rivet 14, said second disk spring being fastened by means of a second plastic ring 20 at the toothed hub 15 or at the flange 6 of the output part 3. The second disk spring 19 extends radially inward (downward in fig. 2) and axially toward the clutch (to the right in fig. 2). The second disk spring can however also run parallel to the disk spring 17, i.e. to the upper right in fig. 2. Instead of the two

plastic rings

18 and 20, a single plastic ring can also be used, which again reduces the construction effort. The second disc spring 19 again increases the friction and the basic hysteresis.

List of reference numerals:

1. dual mass flywheel

2. Input part

3. Output section

4. Arc spring device

5. Cover

6. Secondary flange

7. Disk spring diaphragm

8. Diaphragm ring

9. Primary quality plate

10. Gear ring

11. Axial ring

12. Cover plate

13. Sliding sleeve

14. Rivet

15. Toothed hub

16. Centrifugal pendulum device

17 (first) Belleville spring

18. Plastic ring

19. Second disc spring

20. Plastic ring

R rotation axis

Claims

1. A torsional vibration damper, in particular a dual mass flywheel (1), having an input part (2) and an output part (3) which can be rotated relative to one another against the action of arcuate spring means (4), wherein the arcuate spring means (4) are supported on the one hand at the input part (2) and on the other hand at a flange (6) which is connected to the output part (3), wherein a sealing diaphragm which is designed as a disk spring diaphragm (7) is arranged at the output part (3) or the input part (2) and is in contact with the other part (2 or 3),

it is characterized in that the preparation method is characterized in that,

a disk spring (17) is additionally arranged between the input part (2) and the output part (3).

2. The torsional vibration damper of claim 1,

it is characterized in that the preparation method is characterized in that,

the input part (2) has a cover (5), and the disk spring diaphragm (7) slides at the cover or at a diaphragm ring (8) fixed at the cover.

3. The torsional vibration damper of any of the preceding claims,

it is characterized in that the preparation method is characterized in that,

the disk spring (17) is fixed to the flange (6) or to another element of the output part (3), for example to a hub (15), and bears with its radial and axial outer side in a sliding manner against the cover (5) of the input part (2).

4. The torsional vibration damper of any of the preceding claims,

it is characterized in that the preparation method is characterized in that,

a second disk spring (19) is arranged between the input part (2) and the output part (3).

5. The torsional vibration damper of claim 4,

it is characterized in that the preparation method is characterized in that,

the second disk spring (19) is arranged radially further within the first disk spring (17).

6. The torsional vibration damper of any of the preceding claims,

it is characterized in that the preparation method is characterized in that,

the diaphragm (7) and/or one or more disk springs (17, 19) are made of spring steel.

7. The torsional vibration damper of any of the preceding claims,

it is characterized in that the preparation method is characterized in that,

one or both disk springs (17, 19) are fixed by means of plastic rings (18, 20).

8. The torsional vibration damper of any of the preceding claims,

it is characterized in that the preparation method is characterized in that,

the torsional vibration damper comprises one or more centrifugal pendulum devices (16).

9. The torsional vibration damper of any of the preceding claims,

it is characterized in that the preparation method is characterized in that,

the surface roughness and the material pairing of the disk spring(s) (17, 19) are designed in such a way that a desired coefficient of friction and the associated basic hysteresis are achieved.

10. A disc spring (17, 19) for use in a torsional vibration damper according to any of the preceding claims.