WO2017092754A1

WO2017092754A1 - Torsional vibration damper

Info

Publication number: WO2017092754A1
Application number: PCT/DE2016/200552
Authority: WO
Inventors: Ion Lucian Buzea; Adrian-Constantin Buta
Original assignee: Schaeffler Technologies AG & Co. KG
Priority date: 2015-11-30
Filing date: 2016-11-25
Publication date: 2017-06-08
Also published as: DE112016005449A5; DE102016223426A1

Abstract

The invention relates to a torsional vibration damper (10), in particular a dual-mass flywheel, for torsional vibration damping between a drive shaft of a motor-vehicle motor and a transmission input shaft of a motor-vehicle transmission, comprising a primary mass (14) for introducing a torque, a secondary mass (18) for outputting the torque, which secondary mass can be rotated in relation to the primary mass (14) to a limited extent by means of an energy storage element (16) designed, in particular, as a bow spring, wherein the secondary mass (18) has at least one mounting opening (28) for the axial feed-through of a fastening element, in particular a fastening screw, for fastening the primary mass (14) to the drive shaft of the motor-vehicle motor, and a cover plate (30), which covers the mounting opening (28), wherein the cover plate (30) is releasably clamped to the secondary mass (18) outside of the mounting opening (28). By means of the cover plate (30) releasably clamped to the secondary mass (18) outside of the mounting opening (28), the entry of contaminants through the mounting opening (28) can be avoided, while ease of disassembly is ensured, such that a torsional vibration damper (10) that has a long service life and that is easy to maintain is enabled.

Description

torsional vibration dampers

The invention relates to a torsional vibration damper, in particular two-mass flywheel, with the aid of which torsional vibrations of a drive shaft of an automotive engine can be damped.

For example, from DE 10 2008 004 150 A1 discloses a dual mass flywheel is known, in which for the torsional vibration damping of a crankshaft of a motor vehicle internal combustion engine, a primary mass is coupled via a bow spring with a rotatable relative to the primary mass secondary mass. The bow spring is arranged in a bow spring channel, wherein a channel wall of the bow spring channel is formed by the primary mass. A flange of the secondary mass, which is supported on the channel wall by a friction ring, projects into the bow spring channel.

There is a constant need to increase the life and ease of maintenance of a torsional vibration damper. It is the object of the invention to show measures that allow a torsional vibration damper with a long life and good maintainability.

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

According to the invention, a torsional vibration damper, in particular two-mass flywheel, for torsional vibration damping between a drive shaft of a motor vehicle engine and a transmission input shaft of a motor vehicle transmission, provided with a primary mass for introducing a torque, one about, in particular designed as a bow spring, energy storage element relative to the primary mass limited rotatable secondary mass for discharging the torque, wherein the secondary mass has at least one mounting hole for axially passing a fastener, in particular fastening screw, for fastening tion of the primary mass with the drive shaft of the motor vehicle engine, and a mounting hole covering Cover plate, wherein the cover plate is detachably clamped outside the mounting hole with the secondary mass.

The primary mass can be used to form a receiving channel for receiving the energy storage element, by means of which a receiving volume can be limited, in which the energy storage element is protected against environmental influences, in particular liquids and dust. In particular, the energy storage element via a lubricant, in particular lubricating oil or grease, on a side facing the energy storage element inside of the receiving channel and / or a guide slide along relatively movable. In this case, a sealing device is preferably provided, with the aid of which a projecting into the receiving channel output flange of the secondary mass is sealed against the receiving channel, so that the lubricant can not escape along the output flange. By way of example, the sealing device can have at least one friction ring, which can slide along the outlet flange and / or on the receiving channel during a relative movement of the outlet flange to the receiving channel. Furthermore, it is avoided by the sealing device that contaminants in the form of liquids or dust reach the energy storage element and the friction-reducing lubricating effect of the lubricant is reduced by the contaminants.

In the case of the torsional vibration damper according to the invention, however, the secondary mass, which is in particular on the drive side, has an extent extending radially inward such that a radius range is also covered by the secondary mass in which the fastening means are installed. The sufficient accessibility to the fastening means during assembly is ensured by the at least one mounting opening, wherein in particular for each attachment point of the respective fastening means is provided in a non-twisted neutral position of the secondary mass to the primary mass substantially coaxially arranged mounting opening. The fastening means can be passed axially through the mounting opening. and for example, by a guided through the mounting hole tool, such as a screwdriver, are attached. After mounting the fastening means, the cover plate can be clamped to the secondary mass, whereby the opening cross-section of the mounting hole can be covered by the cover plate. As a result, it can be avoided that soiling through liquids and / or dust can reach an axial region of the torsional vibration damper which is provided radially inward of the energy storage element. Since the contamination can only get into this area, the contaminants can not be moved from there, for example by centrifugal force radially outward to the energy storage element, so that contamination of the energy storage element and / or provided between the flange and the receiving channel sealing device is avoided ,

By attaching the cover plate outside the mounting hole, the associated attachment point remain easily accessible even after installation. This makes it possible, for example, with a tool and / or by hand to suspend the jamming of the cover plate with the secondary mass and dismantle the cover again. By disassembling the cover plate, the fastening means on the then reopened mounting holes are accessible again, so that for maintenance and / or repair purposes, the torsional vibration damper can be easily removed. With the help of the outside of the mounting hole releasably jammed with the secondary cover plate can be avoided with a slight disassembly an entry of dirt on the mounting hole so that torsional vibration damper is made possible with a long life and good maintainability.

The torsional vibration damper may in particular be configured as a dual-mass flywheel, the primary mass can be attached directly or indirectly to a drive shaft of a motor vehicle and the secondary mass can be connected to a clutch unit for coupling a drive shaft of an automotive engine with at least one transmission input shaft. The torsional vibration damper can also be configured as a disk inner damper, for example, as part of a clutch disk of a clutch unit for coupling a drive shaft of a motor vehicle engine with at least one transmission input shaft be. Inn train operation of the motor vehicle engine, a torque can be introduced via the primary mass in the torsional vibration damper and discharged through the secondary mass. In a coasting operation of the motor vehicle engine, a torque can be introduced via the secondary mass into the torsional vibration damper and discharged via the primary mass. In particular, the primary mass and / or the secondary mass may optionally abut on the energy storage element via an intended clearance angle in the circumferential direction in order to be able to transmit the torque via the energy storage element between the primary mass and the secondary mass. The relative rotatability of the secondary mass to the primary mass can be limited by the compressibility of the energy storage element.

The cover plate can be produced in particular by punching from a metal sheet and non-cutting forming. The production costs can be kept low.

In particular, the cover plate has at least one clip element, preferably three clip elements, wherein the clip element is clipped with a latching surface formed by the secondary mass. By the clip element not only a frictional connection, but also a positive connection between the cover and the secondary mass can be made, so that the cover plate does not accidentally dissolve even at sudden high loads from the secondary mass. For disassembly of the cover plate, for example by means of a tool and / or by hand, the clip element can be bent away from the latching surface of the secondary mass to cancel the positive connection. An optionally remaining frictional engagement is in particular so small that the frictional engagement during disassembly and / or assembly can be easily overcome.

Preferably, the clip element protrudes radially outwardly from the rest of the cover plate, wherein the clip element is designed to be resilient radially inward and engages behind the axially facing locking surface in the mounted state. The clip element can thereby spring radially outward to make the clip connection. As a result, the connection of the cover plate with the secondary mass under the influence of centrifugal force is self-reinforcing. Unintentional release of the cover plate From the secondary mass under the influence of centrifugal force is avoided. During assembly, the cover plate can be pushed in the axial direction of the mounting opening until the clip element springs radially outward and engages behind the locking surface to form a positive connection.

Particularly preferably, the secondary mass has a substantially radially inwardly facing connected to the locking surface radial surface, wherein the radial surface to form a locking surface towards the tapered opening cross-section

beveled designed. The radial surface can be designed to be comparable to a funnel and bound radially within a substantially frusto-conical opening volume. The cover plate can thereby be used during assembly without additional tools in the limited by the radial surface opening. The protruding in the radial direction clip elements can be used in the region of the larger diameter of the opening cross-section and automatically bent by the taper of the opening cross-section radially inward until the clip elements after passing the locking surface can automatically spring radially outward. The assembly is simplified.

In particular, the clip element has a protruding disassembly approach for the hand-elastic bending of the clip element radially inward. Through the disassembly approach the clip element remains accessible and is not unreachable and thus disappeared undetachably behind the locking surface. With the aid of the disassembly approach, the clip element can be moved by hand and / or by means of a tool to a radius radially inward on which the clip element is positioned radially inwardly of the catch surface. A positive connection is thereby canceled, so that the cover plate can subsequently be moved away from the assembly opening by an axial relative movement to the secondary mass and can be dismantled.

Preferably, the clip element viewed in the circumferential direction has a substantially mushroom-head-shaped cross-section. The mushroom-shaped cross-section results in an undercut region which allows a good positive connection with the latching surface. An axial relative movement in the assembled state can be easily blocked. Particularly preferably, the secondary mass to a communicating with the environment ventilation opening, wherein the cover plate is jammed in the ventilation opening, wherein in particular the clip element is clipped in the ventilation opening. The cover plate can thereby be fixed in the anyway provided ventilation opening. About the ventilation opening, a part of the cover plate can be led to the outside to cause a clip connection or other releasable positive fit with the secondary mass in the mounted state. The ventilation opening communicates with the outside of the torsional vibration damper environment and not with the interior of the torsional vibration damper, where the energy storage element is arranged. A sealing of the ventilation opening is not required and not wanted. Via the ventilation opening, hot air can escape to the outside, whereby cooling of the torsional vibration damper and / or further connected components of the drive train, for example a friction clutch, can take place by convection.

In particular, the secondary mass radially outside the mounting opening on a particular closed circumferential centering, in particular a machined centering, for centering the cover plate on. The cover plate can thereby be easily positioned in a desired relative position to the mounting opening. Centering via clip elements is not required. In particular, when the centering element is formed by a centering groove produced by machining, tolerance-related inaccuracies in the radial direction can be avoided. The secondary mass can be made in particular by metal casting and still allow a precise relative position of the cover plate.

Preferably, the secondary mass has a central central opening, in particular for storage on the primary mass, wherein the cover plate has an insertion bevel for centering the cover plate at the central opening. The cover plate can thus be easily centered on the secondary mass. At least a first Grobzentrierung during the axial relative movement of the cover plate relative to the secondary mass during assembly is achieved. The introduction bevel preferably runs closed in the circumferential direction, so that a truncated cone-shaped section results. Particularly preferred is the radial extent of the frustoconical portion is so large that a camp over which the secondary mass is stored on the primary mass, in the axial direction to a large extent, in particular completely, is covered. The frusto-conical portion can serve as a splash guard for the camp and at least make it difficult access of contaminants to the camp. Preferably, a clearance fit is provided in the axial direction between the bearing and the end nearest the bearing of the frusto-conical section, so that a labyrinth seal can result between the bearing and the frusto-conical section. Particularly preferably, the secondary mass on a plurality of mounting holes, wherein all mounting holes are covered by the only provided cover plate. As a result, it is not necessary to cover each mounting hole individually by a cover plate. Instead, just a single cover plate is sufficient to close the mounting holes. The number of components is kept low.

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 is a schematic sectional view of a torsional vibration damper,

2 is a schematic sectional view of a cover plate of the torsional vibration damper of FIG. 1,

3 shows a schematic perspective top view of the cover plate from FIG. 2, FIG. 4 shows a schematic sectional view of the torsional vibration damper from FIG. 1 at a first point in time during assembly,

Fig. 5 is a schematic sectional view of the torsional vibration damper of FIG. 1 at a second time in the assembly and

6 shows a schematic sectional view of the torsional vibration damper from FIG. 1 at a third time during assembly.

The illustrated in Fig. 1 designed as a dual mass flywheel torsional vibration damper 10 has a fastening openings 12 with a drive shaft a motor vehicle motor screwed to the primary mass 14, which is limited rotatably coupled to a secondary mass 18 via an energy storage element 16 configured as a spring. The primary mass 14 forms a receiving space 20, in which the energy storage element 16 is arranged. The secondary mass 18 has an output flange 22, which protrudes from radially inward into the receiving space 20, so that at a speed fluctuation, the energy storage element 16 between the output flange 22 and a stop of the primary mass 14 can be compressed. In the illustrated embodiment, the secondary mass 18 has a friction surface 24, so that the secondary mass 18 can simultaneously act as Gegenplat- te a friction clutch on which by means of an axially displaceable pressure plate of the friction clutch coupled to a transmission input shaft of a motor vehicle transmission clutch plate can be frictionally pressed. In addition, the secondary mass 18 is mounted on a hub-shaped region of the primary mass 14 via a bearing 26.

In order to screw the primary mass 14 to the drive shaft, the secondary mass 18 has corresponding mounting openings 28. So that no dirt can reach the energy storage element 16 via the assembly openings 28, the assembly openings 28 are completely covered by a cover plate 30. For this purpose, the cover plate 30 is releasably clamped to the secondary mass 18 outside the assembly opening 28.

As shown in Fig. 2 and Fig. 3, the cover plate 30 has a total of three radially outwardly projecting clip elements 32 which can be used in ventilation openings 34 of the secondary erärmermasse 18 to engage behind a locking surface 36 and a clip connection with the secondary mass 18 train. From the mushroom-shaped clip element 32 is a dismounting approach 38, with the help of the clip connection can be subsequently released. The cover plate 30 additionally has a peripheral circumferential nose 40, which can be used in a corresponding designed as machined centering centering 42. In addition, the cover plate 30 has a frusto-conical projecting bevel 44 in order to roughly precenter the cover plate 30 at a central opening 46 of the secondary mass can. As shown in Fig. 4, the cover plate 30 can be easily inserted by an axial relative movement in the secondary mass 18. In this case, the clip elements 32 are pressed elastically radially inwards from a funnel-like radial surface 48 that tapers in a direction toward the assembly openings and are thereby spring-biased. As shown in Fig. 5, in a further axial relative movement, the cover plate 30 by means of the lead-in bevel 44 and the nose 40 on the secondary mass 18 can be centered. In this case, the cover plate 30 can cover the assembly openings 28 with its region extending in a planar manner between the nose 40 and the insertion bevel 44 substantially in the radial direction. Finally, the clip element 32 can snap into the ventilation opening 34 and thereby engage behind the latching surface 36, as shown in FIG. 6, so that the assembled state of the torsional vibration damper 10 shown in FIG. 1 results. For disassembly of the cover plate 30, the clip member 32 can be pulled out against the spring force by means of the demounting approach 38 from the ventilation opening 34, so that the clip member 32 may abut with its spring force on the radial surface 48 again. Subsequently, the cover plate 30, in particular by means of the dismounting projections 38 are pulled out of the secondary mass 18, whereby the mounting holes 28 are accessible again.

Reference sign list torsional vibration damper

fastening opening

primary mass

Energy storage element

secondary mass

accommodation space

output flange

friction surface

camp

mounting hole

Cover plate

clip member

vent

Rest area

Disassembly approach

nose

centering

insertion bevel

central opening

radial surface

Claims

claims

A torsional vibration damper, in particular a dual-mass flywheel, for the torsional vibration damping between a drive shaft of an automotive engine and a transmission input shaft of a motor vehicle transmission, having a primary mass (14) for introducing a torque,

an energy storage element (16) configured to be deflected in a limited manner relative to the primary mass (14), in particular as a bow spring, for deflecting the torque,

wherein the secondary mass (18) has at least one mounting opening (28) for the axial passage of a fastening means, in particular fastening screw, for fastening the primary mass (14) to the drive shaft of the motor vehicle engine, and

a cover plate (30) covering the mounting opening (28), the cover plate (30) being releasably clamped to the secondary mass (18) outside the mounting opening (28).

Torsional vibration damper according to claim 1, characterized in that the cover plate (30) at least one clip element (32), preferably three clip elements (32), wherein the clip element (32) with a of the secondary mass (18) formed locking surface (36) is clipped ,

Torsional vibration damper according to claim 2, characterized in that the clip element (32) protrudes radially outward from the rest of the cover plate (30), wherein the clip element (32) is resiliently designed radially inward and in the assembled state, the axially facing locking surface (36 ) engages behind.

Torsional vibration damper according to claim 2 or 3, characterized in that the secondary mass (18) has a substantially radially inwardly facing with the detent surface (36) connected to the radial surface (48), wherein the radial surface (48) for forming a latching surface (36) out tapering Opening cross-section is designed tapered.

5. torsional vibration damper according to one of claims 2 to 4, characterized in that the clip element (32) has a projecting disassembly approach (38) for manually elastic bending of the clip element (32) radially inward.

6. torsional vibration damper according to one of claims 2 to 5, characterized in that the clip element (32) viewed in the circumferential direction has a substantially mushroom-shaped cross-section.

7. torsional vibration damper according to one of claims 1 to 6, characterized in that the secondary mass (18) has a communicating with the environment ventilation opening (34), wherein the cover plate (30) in the ventilation opening (34) is clamped, in particular the clip element ( 32) in the ventilation opening (34) is clipped.

8. Torsional vibration damper according to one of claims 1 to 7, characterized in that the secondary mass (18) radially outward to the mounting opening (28) in particular a closed circumferential centering element (42), in particular a machined centering, for centering the cover plate (30) ,

9. torsional vibration damper according to one of claims 1 to 8, characterized in that the secondary mass (18) has a central central opening (46), in particular for storage on the primary mass (14), wherein the cover plate (30) has an insertion bevel (44) Centering the cover plate (30) at the central opening (46).

10. torsional vibration damper according to one of claims 1 to 9, characterized in that the secondary mass (18) a plurality of mounting holes (28) points, wherein all mounting holes (28) are covered by the only provided cover plate (30).