DE102018112326A1 - torsional vibration dampers - Google Patents

Abstract

It is a torsional vibration damper (10) for damping torsional vibrations in a drive train of a motor vehicle provided with a about an axis of rotation (12) rotatable primary mass (14) relative to the primary mass (14) limited rotatable secondary mass (28), one on the primary mass (14) and at the secondary mass (28) abuttable energy storage element (24) for coupling the primary mass (14) with the secondary mass (28), wherein the energy storage element (24) in one of the primary mass (14) at least partially limited receiving space (22) is arranged, and one with secondary mass (28) connected and on the primary mass (14) tightly fitting sealing membrane (38) for sealing the receiving space (22), wherein the secondary mass (28) directly or indirectly on the primary mass (14) abuttable axial stop (42) for limiting a maximum tension of the sealing membrane (38) with an axial offset of the secondary mass (28) to the primary mass (14) t. This reduces the risk of damage to torsional vibration dampers (10) during repair and maintenance work.

Description

The invention relates to a torsional vibration damper, in particular two-mass flywheel, pulley decoupler or disc damper, with the help of which occurring in a drive train of a motor vehicle torsional vibrations can be damped.

For example DE 10 2015 221 022 A1 is designed as a dual mass flywheel torsional vibration damper with a primary mass and a limited to the primary mass via a bow spring rotatable secondary mass, wherein the secondary mass has a projecting into one of the primary mass receiving channel for receiving the bow spring projecting output flange. The receiving channel may be sealed by a sealed with the secondary mass and sliding off on a cover of the primary mass sealing membrane.

There is a constant need to avoid damage to torsional vibration dampers during repair and maintenance.

It is the object of the invention to show measures that reduce the risk of damage to torsional vibration dampers during repair and maintenance.

The object is achieved by a torsional vibration damper with the features of claim 1. Preferred embodiments of the invention are set forth in the subclaims and the following description, each of which individually or in combination may constitute an aspect of the invention.

According to the invention, a torsional vibration damper, in particular a dual mass flywheel, pulley decoupler or disk damper, is provided for damping torsional vibrations in a drive train of a motor vehicle with a primary mass rotatable about a rotational axis, a secondary mass which is rotatable relative to the primary mass, an energy storage element which can be hit on the primary mass and on the secondary mass, in particular bow spring, for coupling the primary mass with the secondary mass, wherein the energy storage element is arranged in one of the primary mass at least partially receiving space, and connected to secondary mass and, in particular with bias, on the primary mass, in particular a cover of the primary mass, sealingly fitting sealing membrane for sealing the receiving space, wherein the secondary mass a directly or indirectly abuttable on the primary mass axial stop to limit a maximum tension the sealing membrane has an axial displacement of the secondary mass to the primary mass.

If during repair and / or maintenance of the torsional vibration damper to be dismantled, one of the rotatably coupled to the torsional vibration damper shaft is pulled away in the axial direction. In this case, even a small angular displacement is sufficient for the primary mass or the secondary mass to be clamped on its associated shaft and taken along in the axial direction, so that an axial relative movement of the secondary mass to the primary mass occurs. In this axial relative movement of the secondary mass to the primary mass, however, the, in particular designed in the manner of a diaphragm spring, diaphragm spring is always braced.

However, due to the axial stop formed by the secondary mass, significant plastic deformation or destruction of the diaphragm spring can be prevented by the axial stop blocking a further axial relative movement of the secondary mass to the primary mass. Before at a occurring during the disassembly of the torsional vibration damper relative axial movement of the secondary mass to the primary mass a maximum voltage provided for the diaphragm spring is exceeded, the axial stop can strike directly or indirectly on the primary mass. The primary mass can have a disk with which a cover can be connected in order to delimit a substantially annular receiving space for the energy storage element, wherein the axial stop can strike, in particular, against an inner side of the lid facing the receiving space. If the axial stop of the secondary mass strikes against the primary mass, the primary mass can be taken along with a further introduction of an axial force into the secondary mass, or at least one further axial relative movement can be blocked. In any case, further deformation of the sealing membrane can be blocked. If an axial relative movement of the secondary mass to the primary mass occurs during disassembly of the torsional vibration damper, in this case abutting the primary mass axial stop of the secondary mass can prevent damage to the diaphragm spring by excessive tension, so that the risk of damage to torsional vibration dampers in repair and Maintenance work is reduced.

The primary mass and the secondary mass arranged to be rotatably coupled to the primary mass, which is configured in particular as a bow spring, can form a mass-spring system which dampens rotational irregularities in the rotational speed and in the torque of the drive power generated by a motor vehicle engine in a certain frequency range can. Here, the mass moment of inertia of the primary mass and / or the secondary mass and the spring characteristic of the energy storage element may be selected such that vibrations in the frequency range of the dominant engine orders of the motor vehicle engine can be damped. The mass moment of inertia of the primary mass and / or the secondary mass can be influenced in particular by an attached additional mass. The primary mass may have a disk, with which a lid may be connected, whereby the substantially annular receiving space for the energy storage element may be limited. For example, the primary mass can strike tangentially on the energy storage element via indentations projecting into the receiving space. In the receiving space, the output flange of the secondary mass can protrude, which can strike tangentially at the opposite end of the energy storage element. When the torsional vibration damper is part of a dual mass flywheel, the primary mass may include a flywheel coupleable to a drive shaft of an automotive engine. If the torsional vibration damper pulley as a decoupler part of a pulley assembly for driving ancillary components of a motor vehicle by means of a traction means, the primary mass can form a pulley on the radially outer surface of the traction means, in particular a V-belt, can engage in torque transmission. When the torsional vibration damper is used as a disc damper, in particular a clutch disc of a friction clutch, the primary mass may be coupled to a friction lining bearing disc portion, while the secondary mass may be coupled to a transmission input shaft of a motor vehicle transmission.

In particular, in a maximum offset position in which the axial stop is struck, the sealing membrane has a maximum stress σ _max , wherein the maximum stress σ _{max is} less than the upper yield strength R _eH and / or less than the yield strength R _p0,2 at 0, 2% plastic deformation, in particular σ _max / R _eH ≤ 0.90, preferably σ _max / R _eH ≤ 0.80 and particularly preferably σ _max / R _eH ≤ 0.70 and / or σ _max / R _{p 0.2} ≦ 0.90, preferably σ _max / R _{p0.2 ≦} 0.80, and more preferably σ _max / R _{p0.2 ≦} 0.70. As a result, a significant plastic deformation of the sealing membrane during disassembly of the torsional vibration damper can be reliably avoided. At the same time a significant spring travel in the axial direction can be allowed for the sealing membrane, so that the axial stop of the secondary mass to the primary mass in the axial direction can be positioned far enough apart to safely avoid unintentional frictional sliding contact in normal operation.

Preferably, the secondary mass has a projecting into the receiving space output flange for tangential striking the energy storage element, wherein from the output flange a tab is bent out to form the axial stop. The axial stop need not be configured as a separate component, but can be formed by the anyway provided output flange. The number of components can be kept low. To form the tab, for example, from a radially outer edge radially inwardly extending slots are punched into the output flange and thereafter only radially inwardly tethered tab are bent out of the plane of the Ausgangsflanschs until the bent-out tab the desired maximum axial displacement of the secondary mass Limit primary mass during disassembly. Since the output flange can transmit a significant torque, the output flange usually has a correspondingly large axial thickness, so that the bent-out tab behaves substantially rigidly at a striking the axial stop at the disassembly forces expected during disassembly and not yielding elastically. The maximum deformation of the sealing membrane can be safely limited.

Particularly preferably, the tab is bent from the output flange, wherein the axial stop by one, in particular substantially flat; Axial side of the tab is formed. The tab need not be bent by 90 ° in order to form with its narrow side the axial stop. Instead, it is already sufficient to expose the tab by a bend in the axial direction and form the axial stop by the flat axial side. The manufacturing process is simplified. In addition, it is possible to form the axial stop over a large area.

In particular, two radially opposite tabs are provided. As a result, tilting of the output flange can be avoided when striking the axial stop. The risk that the secondary mass is tilted and / or jammed during disassembly is thereby reduced. Instead, an already tilted secondary mass can be correctly aligned again via the axial stops striking the primary mass. It is also possible to provide three, four or more evenly distributed in the circumferential direction in each case an axial stop forming tabs to minimize tilting of the output flange.

Preferably, the output flange has a disk body and at least one of the disk body radially outwardly projecting Stop lug for tangential abutment on the energy storage element, wherein the tab to the stop lug offset in the circumferential direction is formed by the disk body. The tabs can thereby be provided in areas of the disk body, in which the outgoing of the stop approaches power flow is not affected in the torque transmission. A weakening of the disk body in the vicinity of the stop lug, in particular radially inside the stop lug, can be avoided.

Particularly preferably, the sealing membrane is supported via a sliding ring on the primary mass, wherein the axial stop for striking the sliding ring, in particular at a centering edge of the sliding ring, is configured. The sliding ring may for example be made of a plastic material, so that the sliding ring can dampen the impact of the axial stop. A hard steel / steel contact, which could possibly lead to plastic deformation and the formation of notches, can be avoided.

In particular, the secondary mass, in particular the output flange, to the primary mass in the radial direction movable, in particular uncentered and / or unsupported configured. Due to the lack of centering and / or lack of storage of the secondary mass of the primary mass production costs can be reduced. A centering of the Sekundärmassa on the primary mass, for example, by a centering of the respective waves, with which the primary mass and the secondary mass are connected take place. If one of the shaft is removed for disassembly of the torsional vibration damper, a frictional coupling with the shaft to be withdrawn is basically possible due to the lack of centering and the basic relative mobility in the radial direction. However, the axial stop can ensure that an axial offset of the secondary mass to the primary mass is limited and damage to the sealing membrane is avoided.

• 1: eine schematische Schnittansicht eines Drehschwingungsdämpfers und
• 2: eine schematische Draufsicht auf einen Ausgangsflansch des Drehschwingungsdämpfers aus 1.

The invention will now be described by way of example with reference to the accompanying drawings with reference to preferred embodiments, wherein the features shown below, both individually and in combination may represent an aspect of the invention. Show it:

• 1 : A schematic sectional view of a torsional vibration damper and
• 2 : A schematic plan view of an output flange of the torsional vibration damper 1 ,

The in 1 on the example of a dual mass flywheel for torsional vibration damping in a drive train of a motor vehicle shown torsional vibration damper 10 has one about a rotation axis 12 rotatable primary mass 14 on. The primary mass 14 has a drive shaft 16 an automotive engine screwed disc-shaped flywheel 18 and one with the flywheel 18 welded lid 20 on, which is an annular receiving space 22 limit, in which designed as a bow spring energy storage element 24 is arranged.

The primary mass 14 can over in the recording room 22 protruding indentations tangentially at one end of the energy storage element 24 attacks. At another end, the energy storage element 24 for transmitting torque to one in the receiving space 22 radially projecting output flange 26 one to the primary mass 14 limited rotatable secondary mass 28 strike tangentially. The secondary mass 28 has one with the output flange 26 riveted additional mass 30 and one with the output flange 26 riveted output hub 32 on. The output hub 32 can radially inside a spline 34 over which the output hub 32 torque transmitting with a leading to a motor vehicle transmission of the motor vehicle shaft 36 , For example, a transmission input shaft of the motor vehicle transmission, can be rotatably connected. With the secondary mass 28 is additionally one on the lid 20 sliding sealing membrane 38 riveted to the recording room 22 seal.

From the output flange 26 is a bent tab 40 bent out, the one on its flat axial side to the lid 20 pointing axial stop 42 formed. When disassembling the torsional vibration damper 10 the wave 36 to be deducted in the axial direction and the secondary mass 28 due to an angular misalignment in the spline 34 frictionally engaged on the shaft 36 the wave can hang 36 the secondary mass 28 in the axial direction. Before the sealing membrane 38 This is so strong braced that the sealing effect of the sealing membrane 38 Significant plastic deformation can occur, the axial stop 42 on the primary mass 14 strike and block another axial relative movement. For this purpose, the axial stop 42 at one between the sealing membrane 38 and the lid 20 the primary mass 14 provided sliding ring 44 attacks. The sliding ring 44 can be an axial direction across the thickness of the sealing membrane 38 also projecting centering 46 have, at which the axial stop 42 can strike without the sealing membrane 38 to contact.

As in 2 shown, the output flange 26 a disk body 48 have, of the example, two stop approaches 50 protrude radially outward, the tangent to the energy storage element 24 can strike. In the circumferential direction to the stop approaches 50 each offset from two radially inwardly extending slots from a radially outer edge 52 stamped, between each of which the tab 40 formed and out of the plane of the disk body 48 bent out bent.

LIST OF REFERENCE NUMBERS

10

torsional vibration dampers

12

axis of rotation

14

primary mass

16

drive shaft

18

flywheel

20

cover

22

accommodation space

24

Energy storage element

26

output flange

28

secondary mass

30

additional mass

32

output hub

34

splines

36

wave

38

sealing membrane

40

flap

42

axial stop

44

sliding ring

46

centering

48

washer body

50

stop approach

52

slot

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• DE 102015221022 A1 [0002]

Claims (8)

Torsional vibration damper, in particular two-mass flywheel, pulley decoupler or disc damper, for damping torsional vibrations in a drive train of a motor vehicle, with a primary mass (14) rotatable about an axis of rotation (12), a relatively limited to the primary mass (14) rotatable secondary mass (28), one on the primary mass (14) and on the secondary mass (28) abutsable energy storage element (24), in particular bow spring, for coupling the primary mass (14) with the secondary mass (28), wherein the energy storage element (24) in one of the primary mass (14 ) is arranged at least partially limited receiving space (22), and a sealing membrane (38) sealingly attached to the primary chamber (14), in particular a cover (20) of the primary mass (14), which is connected to a secondary mass (28) and, in particular, prestressed, for sealing the receiving space (22), wherein the secondary mass (28) has an axial stop (42) which can be abutted directly or indirectly on the primary mass (14) for limiting a maximum tension of the sealing membrane (38) with an axial displacement of the secondary mass (28) to the primary mass (14). Torsional vibration damper after Claim 1 characterized in that in a maximum offset position, in which the axial stop (42) is struck, the sealing membrane (38) has a maximum stress σ _max , wherein the maximum stress σ _max less than the upper yield strength R _eH and / or less than that _Yield strength R _p0.2 at 0.2% plastic deformation, wherein in particular σ _max / R _{eH ≦} 0.90, preferably σ _max / R _{eH ≦} 0.80 and particularly preferably σ _max / R _{eH ≦} 0.70 and / or σ _max / R _p0.2 ≤ 0.90, preferably σ _max / R _p0.2 ≤ 0.80 and more preferably σ _max / R _p0.2 ≤ 0.70. Torsional vibration damper after Claim 1 or 2 characterized in that the secondary mass (28) in the receiving space (22) projecting output flange (26) for tangential abutment on the energy storage element (24), wherein from the output flange (26) has a tab (40) for forming the axial stop (42 ) is bent out. Torsional vibration damper after Claim 3 characterized in that the tab (40) is bent from the output flange (26), wherein the axial stop (42) by one, in particular substantially flat; Axial side of the tab (40) is formed. Torsional vibration damper after Claim 3 or 4 characterized in that two in the radial direction opposite tabs (40) are provided. Torsional vibration damper after one of Claims 3 to 5 characterized in that the output flange (26) has a disk body (48) and at least one of the disk body (48) radially outwardly projecting stop lug (50) for tangential abutment against the energy storage element (24), wherein the tab (40) to the Stop lug (50) offset in the circumferential direction of the disk body (48) is formed. Torsional vibration damper after one of Claims 1 to 6 characterized in that the sealing membrane (38) via a slide ring (44) on the primary mass (14) is supported, wherein the axial stop (42) for abutment against the sliding ring (44), in particular at a centering edge (46) of the sliding ring (44 ), is configured. Torsional vibration damper after one of Claims 1 to 7 characterized in that the secondary mass (28), in particular the output flange (26), to the primary mass (14) in the radial direction movable, in particular uncentered and / or unsupported, is configured.

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