DE102017113043A1 - Drive wheel with torsional vibration damping device - Google Patents

Abstract

The invention relates to a drive wheel with a traction sheave having a Zugmittelanbindungsbereich and a shaft connection area, which is rotatable against the damping effect of at least one torsional vibration damping device relative to the Zugmittelanbindungsbereich; wherein the torsional vibration damping device is arranged in a space formed by the Zugmittelanbindungsbereich and the shaft connection area; wherein at least a first seal with an elastomer sealing lip for sealing the gap with respect to an external environment is arranged such that a sealing effect of the first seal increasingly reduces with increasing rotational speed of the drive wheel.

Description

The invention relates to a drive wheel with a torsional vibration damping device. The drive wheel comprises a drive pulley having a traction means connection region and a shaft connection region which, contrary to the damping effect of at least one torsional vibration damping device, can be rotated relative to the traction device connection region; wherein the torsional vibration damping device is arranged in a gap formed by the Zugmittelanbindungsbereich and the shaft connection area.

The drive wheel is in particular for connecting a pulley on a crankshaft of a drive machine z. B. a motor vehicle provided (ie a Riemenscheibenentkoppler). The drive wheel can also form a two-mass flywheel.

From the DE 10 2013 206 444 A1 Such a drive wheel is known, where it is sealed by means of a sealing and positioning device on the one hand (eg with a lubricant at least partially filled) gap (there spring receiving space) against an external environment and on the other hand, the drive disk is positioned in the axial direction. For this purpose, a spring element is arranged between the Zugmittelanbindungsbereich and the shaft connection area, that the areas braced in an axial direction to each other. The spring element is held by friction rings (without elastic sealing lip), which also ensure a sealing effect.

The requirements for the sealing of the gap are very high. So are carried out due to the higher demands a variety of contamination test, z. Eg, splash water tests, mud brine tests, dust tests, salt spray tests, water tests. In particular, in the Wat test, in which the drive wheel is placed in a water bath and the present sealing concept is acted upon by a water column, the gap of the drive wheel fills regularly.

From the EP 2 628 976 A1 a drive wheel is known in which a seal with a sealing lip forms an elastic sealing contact with the sealing surface of the opposite wall. For such a sealing lip, however, a lubrication of the sealing lip is required because otherwise a rapid wear of the sealing lip is to be expected as a result of friction.

On this basis, the present invention has the object, at least partially overcome the disadvantages discovered in the prior art and in particular to provide a drive wheel, in which an effective but possible wear-free sealing of the gap is made possible.

The object is solved by the features of independent claim 1. Advantageous developments are the subject of the dependent claims. The features listed individually in the claims can be combined in a technologically meaningful manner and can be supplemented by explanatory facts from the description and details of the figures, with further embodiments of the invention are shown.

The invention relates to a drive wheel having a traction sheave having a Zugmittelanbindungsbereich and a shaft connection area, which is against the damping effect of at least one torsional vibration damping device relative to the Zugmittelanbindungsbereich (in a circumferential direction) rotatable. The torsional vibration damping device is arranged in a space formed by the Zugmittelanbindungsbereich and the shaft connection area. At least a first seal with an elastically deformable sealing lip is arranged to seal the gap with respect to an external environment such that a sealing effect of the first seal increasingly reduces with increasing rotational speed of the drive wheel.

With regard to the structure of the drive wheel z. B. on the above-mentioned DE 10 2013 206 444 A1 directed.

In particular, at least one second seal with an elastically deformable sealing lip for sealing the intermediate space with respect to an external environment is arranged such that a sealing effect of the second seal increasingly reduces with increasing rotational speed of the drive wheel.

Preferably, at least the first seal or the second seal (or both seals) is a V-seal, a gamma seal or radial lip seal whose elastically deformable sealing lips with increasing rotational speed of the drive wheel due to the centrifugal force occurring from a sealing surface of the seal opposite lying wall is moved away.

The aforementioned seals (V-seal, gamma seal, radial lip seal) are each known annular seals with elastically deformable (annular) sealing lip, wherein the sealing lip is usually formed by an elastomer.

A radial lip seal has, in particular, a base body and two sealing lips extending from the base body to an opposite wall. The sealing lips extend from the main body towards the opposite wall and increasingly move away from each other.

The seals and in particular the sealing lips are now arranged so that they move away with increasing rotational speed of the drive wheel due to the occurring and increasing centrifugal force of a sealing surface of the seal opposite wall. Thus, the pressure acting on the sealing lip against the wall pressure is increasingly reduced, so that the friction occurring and thus the wear of the sealing lip (increasingly) is reduced.

In particular, the Zugmittelanbindungsbereich and the shaft connection area are arranged braced by a spring element in an axial direction to each other. The spring element is z. B. a plate spring. The spring element extends in particular in the circumferential direction circumferentially and between a connection to the Zugmittelanbindungsbereich and a connection to the shaft connection area at least in the radial direction. By the spring force of the spring element of the Zugmittelanbindungsbereich opposite the shaft connection area, the z. B. is bolted to a crankshaft, fixed in the axial direction.

In particular, at least the first seal is arranged between the spring element and the intermediate space. This can be kept at least from the first seal by the spring element, in particular coarser dirt.

In particular, at least the first seal is arranged and configured such that a sealing effect increases at a higher pressure in the environment than in the gap. In particular, the contact pressure is increased at the sealing lip when z. B. from the outer environment a water column acts on the sealing lip. Therefore, the sealing concept proposed here has a very good sealing effect even when the drive wheel is stationary. Furthermore, the effect may occur that after a certain period of operation the air in the intermediate space heats up strongly (eg to 120 degrees Celsius). Now meets cold water (for example, in a flow passage of a motor vehicle) on the drive wheel, the air in the space is strongly cooled and contracts. This could actively air / water / dirt from the outside environment are sucked into the gap. However, the sealing lips are arranged so that suck at a negative pressure in the intermediate space, the sealing lips on the sealing surface of the opposite wall and thus prevent ingress of water and dirt.

Preferably, at least the first seal is arranged and designed so that lifts off the sealing lip from a minimum speed and a sealing effect is no longer present. It is assumed that above a certain minimum speed water and dirt are thrown to the outside and from the sealing surface, so that a sealing effect is not necessarily required. In particular, it is proposed that the minimum rotational speed is 3,000 revolutions per minute, preferably 4,000, particularly preferably 5,000.

In particular, at least the first seal is operated without lubrication of the sealing lip. Lubrication (eg with grease) of at least the first seal should not be required due to the reduced friction with the increasing speed.

In particular, the shaft connection region is designed in several parts, wherein the intermediate space is sealed off from the external environment by at least one sealing element between the components of the shaft connection region.

In particular, the at least one sealing element is an O-ring.

The comments on the first seal apply in particular equally to the second seal.

By way of precaution, it should be noted that the numerical terms used here ("first", "second",...) Primarily (only) serve to distinguish a plurality of similar objects, variables or processes, ie in particular no dependence and / or order of these objects, quantities or mandate processes to one another. If a dependency and / or order are required, this is explicitly stated here or it obviously results for the person skilled in the art when studying the concretely described embodiment.

• 1: eine erste Ausführungsvariante des Triebrades in einer Seitenansicht im Schnitt; und
• 2: eine zweite Ausführungsvariante des Triebrades in einer Seitenansicht im Schnitt.

The invention and the technical environment will be explained in more detail with reference to FIGS. It should be noted that the invention should not be limited by the embodiments shown. In particular, unless explicitly stated otherwise, it is also possible to extract partial aspects of the facts explained in the figures and to combine them with other components and findings from the present description and / or figures. In particular, it should be noted that the figures and in particular the illustrated proportions are only schematic. The same reference numerals designate the same objects, so that explanations if necessary other figures can be used in addition. Show it:

• 1 a first embodiment of the drive wheel in a side view in section; and
• 2 : A second embodiment of the drive wheel in a side view in section.

1 shows a first embodiment of the drive wheel 1 in a side view in section. The drive wheel 1 includes a Zugmittelanbindungsbereich 2 having drive disk 3 and a shaft connection area 4 , which is contrary to the damping effect of at least one torsional vibration damping device 5 relative to the Zugmittelanbindungsbereich 2 (in a circumferential direction 19 ) is rotatable. The torsional vibration damping device 5 is in one by the Zugmittelanbindungsbereich 2 and the shaft connection area 4 formed gap 6 arranged. At least a first seal 7 with an elastically deformable sealing lip 8th is to seal the gap 6 towards an external environment 9 arranged such that a sealing effect of the first seal 7 with increasing speed of the drive wheel 1 increasingly reduced.

Next is a second seal 10 with an elastically deformable sealing lip 8th for sealing the gap 6 towards an external environment 9 arranged such that a sealing effect of the second seal 10 with increasing speed of the drive wheel 1 increasingly reduced.

Here are the first seal 7 and the second seal 10 designed as a gamma seal whose elastically deformable sealing lips 8th with increasing speed of the drive wheel 1 due to the occurring centrifugal force 11 from a sealing surface 12 the seal 7 . 10 opposite wall 13 be moved away.

The gamma seals 7 . 10 are each known annular seals with elastically deformable (annular) sealing lip 8th , wherein the sealing lip 8th usually formed by an elastomer.

The seals 7 . 10 and the sealing lips 8th are arranged so that they increase with the speed of the drive wheel 1 due to the occurring and increasing centrifugal force 11 from a sealing surface 12 the seal 7 . 10 opposite wall 13 move away. This is the on the sealing lip 8th against the wall 12 acting pressure is increasingly reduced, so that also the friction occurring and thus the wear of the sealing lip 8th (increasingly) reduced.

The Zugmittelanbindungsbereich 2 and the shaft connection area 4 are by a spring element 14 in an axial direction 15 arranged clamped to each other. The spring element 14 is a plate spring. The spring element 14 extends in the circumferential direction 19 circumferential and between a connection to the Zugmittelanbindungsbereich 2 and a connection to the shaft connection area 4 at least in the radial direction 18 , At the connection to the shaft connection area 4 is a friction ring 20 arranged, in contrast to the seals 7 . 10 no elastically deformable sealing lip 8th having. By the spring force of the spring element 14 becomes the Zugmittelanbindungsbereich 2 opposite the shaft connection area 4 that's about the screw connection 23 z. B. is bolted to a crankshaft, in the axial direction 15 fixed.

The first seal 7 is between the spring element 14 and the gap 6 arranged. This can be achieved by the spring element 14 coarser dirt at least from the first seal 7 be kept away.

The seals 7 . 10 are arranged and designed so that at a higher pressure in the environment 9 as in the gap 6 increases a sealing effect. In particular, the contact pressure on the sealing lip 8th increased if z. B. from the outside environment 9 a water column on the sealing lip 8th acts. Therefore, the proposed here sealing concept even when the drive wheel 1 a very good sealing effect. Further, the effect may occur that after a certain period of operation, the air in the space 6 Heavily heated (eg to 120 degrees Celsius). Now hits cold water (for example, in a river crossing a motor vehicle) on the drive wheel 1 gets the air in the gap 6 strongly cooled and contracts. This could be active air / water / dirt from the outside environment 9 in the gap 6 be sucked into it. The sealing lips 8th however, are arranged so that at a negative pressure in the gap 6 the sealing lips 8th to the sealing surface 12 the opposite wall 13 suck in and prevent ingress of water and dirt.

A sliding washer 21 is between one with the Zugmittelanbindungsbereich 2 connected lid 26 and the shaft connection area 4 arranged.

Visible is the shaft connection area 4 executed in several parts, with the gap 6 towards the outside environment 9 by two sealing elements designed as O-rings 16 between the components of the shaft connection area 4 is sealed. This can be done via the riveted joint 22 the components of the shaft connection area 4 no water or dirt in the gap 6 penetration.

2 shows a second embodiment of the drive wheel 1 in a side view in section. On the comments too 1 will be referred. In contrast to 1 is the first seal 7 executed here as a radial lip seal. A radial lip seal has a main body 25 on and two starting from the main body 25 to an opposite wall 13 extending sealing lips 8th , The sealing lips 8th extend from the main body 25 towards the opposite wall 13 and increasingly move away from each other. At least on the left of the two sealing lips 8th apply the above statements.

Next is the spring element here 14 at the connection to the shaft connection area 4 and at the connection to the Zugmittelanbindungsbereich 2 , here on the lid 26 , on each friction ring 20 arranged, in contrast to the seals 7 . 10 no elastically deformable sealing lip 8th having.

A sliding washer 21 is between the Zugmittelanbindungsbereich 2 and the shaft connection area 4 arranged. One with the Zugmittelanbindungsbereich 2 connected lid 26 at least partially forms the gap 6 and extends to the friction ring 20 with the spring element 14 connected is.

Again, the shaft connection area 4 executed in several parts, with the gap 6 towards the outside environment 9 by two sealing elements designed as O-rings 16 between the components of the shaft connection area 4 is sealed. Here are the sealing elements 16 each in grooves of the washer 24 arranged. This can be done via the screw connection 23 the components of the shaft connection area 4 no water or dirt in the gap 6 penetration.

LIST OF REFERENCE NUMBERS

1

Triebrad

2

Zugmittelanbindungsbereich

3

drive Windscreen

4

Shaft connection area

5

Torsional vibration damping device

6

gap

7

first seal

8th

sealing lip

9

Surroundings

10

second seal

11

centrifugal

12

sealing surface

13

wall

14

spring element

15

axial direction

16

sealing element

17

axis of rotation

18

radial direction

19

circumferentially

20

friction ring

21

bearings

22

rivet

23

screw

24

washer

25

body

26

cover

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 102013206444 A1 [0003, 0009]
• EP 2628976 A1 [0005]

Claims (10)

Drive wheel (1) with a traction sheave (3) having a traction means connection region (2) and a shaft connection region (4) which is rotatable against the damping effect of at least one torsional vibration damping device (5) relative to the traction means connection region (2); wherein the torsional vibration damping device (5) in a by the Zugmittelanbindungsbereich (2) and the Wellenanbindungsbereich (4) formed gap (6) is arranged; wherein at least a first seal (7) with an elastically deformable sealing lip (8) for sealing the intermediate space (6) with respect to an external environment (9) is arranged such that a sealing effect of the first seal (7) with increasing rotational speed of the drive wheel ( 1) increasingly reduced. Drive wheel (1) to Claim 1 , wherein at least one second seal (10) with an elastically deformable sealing lip (8) for sealing the gap (6) relative to an external environment (9) is arranged such that a sealing effect of the second seal (10) with increasing speed of the drive wheel (1) increasingly reduced. Drive wheel (1) according to one of the preceding claims, wherein at least the first seal (7) or the second seal (10) is a V-seal, a gamma seal or a radial lip seal whose sealing lips (8) with increasing rotational speed of the drive wheel ( 1) due to the centrifugal force (11) from a sealing surface (12) of the seal (7, 10) opposite the wall (13) is moved away. Drive wheel (1) according to one of the preceding claims, wherein the Zugmittelanbindungsbereich (2) and the shaft connection area (4) by a spring element (14) in an axial direction (15) are arranged braced to each other. Drive wheel (1) to Claim 4 , wherein at least the first seal (7) between the spring element (14) and the intermediate space (6) is arranged. Drive wheel (1) according to one of the preceding claims, wherein at least the first seal (7) is arranged and designed so that at a higher pressure in the environment (9) than in the intermediate space (6) increases a sealing effect. Drive wheel (1) according to one of the preceding claims, wherein at least the first seal (7) is arranged and designed so that from a minimum speed, the sealing lip (8) of a sealing surface (12) of the seal (7, 10) opposite wall (13) takes off and a sealing effect is no longer present. Drive wheel (1) according to one of the preceding claims, wherein at least the first seal (7) without lubrication of the sealing lip (8) is operated. Drive wheel (1) according to one of the preceding claims, wherein the shaft connection region (4) is designed in several parts, wherein the intermediate space (6) relative to the outer environment (9) by at least one sealing element (16) between the components of the shaft connection region (4) is sealed , Drive wheel (1) to Claim 9 wherein the at least one sealing element (16) is an O-ring.

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