DE102012012902A1 - Leveling Module - Google Patents

Abstract

The invention relates to an air spring module 1 for suspension and damping of vibrations of a motor vehicle chassis, with. a lid 4 and? an air-tight rolling bellows 6 attached thereto, which at least partially delimits a working space 7 filled with compressed air; a rolling piston 8 which is fixed to a cylinder tube 10 of the shock absorber 3 and on which the rolling bellows 6 unrolls; a damper bearing 16 provided for sealing the working space 7, which connects a piston rod 13 of the shock absorber 3 to the cover 4, the damper bearing 16 being arranged in the cover 4 and subjected on the one hand to the ambient pressure and on the other hand to the air spring pressure; an auxiliary spring 14, which is arranged concentrically to the piston rod 13 and is guided in a guide ring 15, which is fixedly connected to the cover 4 or provided integrally with the cover 4; wherein the cylinder tube 10 of the shock absorber 3 is attached at a first end via a damper fork 11 to a suspension and at a second end on an end face has a bore for the piston rod 13, wherein at almost complete deflection of the air spring module 1, the end face of the cylinder tube 10th supported on the auxiliary spring 14. According to the invention it is proposed that the damper bearing 16 has a arranged in the cover 4, sealed outer ring 18 with a radially inwardly facing, circumferential projection 19 and arranged on the piston rod 13 inner ring 20, which are connected by means of an elastomeric ring 21, wherein the circumferential projection 19 is surrounded on both sides by a metal disk 22, 23 connected to the piston rod 13 with the interposition of an elastic component 24, 25.

Description

The invention relates to an air spring module consisting of an air spring and a shock absorber for suspension and damping of vibrations of a motor vehicle undercarriage, with a lid and an attached airtight rolling bellows, which at least partially limits a working space filled with compressed air, a rolling piston, which on a cylinder tube of the shock absorber is fixed and on which rolls of the rolling bellows, provided for sealing the working space damper bearing which connects a piston rod of the shock absorber with the lid, wherein the damper bearing is arranged in the lid and on the one hand with the ambient pressure and on the other hand acted upon by the air spring pressure, an additional spring, which is arranged concentrically to the piston rod and is guided in a guide ring, which is fixedly connected to the cover or provided with the lid in one piece, wherein the cylinder tube of the shock absorber at a first end via a Dämpferg Abel is attached to a suspension and at a second end on an end face has a bore for the piston rod, wherein supported at almost complete deflection of the air spring module, the end face of the cylinder tube to the auxiliary spring.

• 1) vollständig außerhalb des Druckraums, also in der Umgebung,
• 2) vollständig innerhalb des Druckraums und
• 3) an der Trennstelle zwischen Arbeitsraum (Druckraum) und Umgebung.

Dumper bearings in cars have the task of filtering out high-frequency excitations - due to the road surface - and thus avoid the system-related inertia of the hydraulic shock absorber, which would have a negative effect on ride comfort. This applies to all types of air spring modules. In the case of steel suspension, the damper bearing is subjected to the same pressure on the top and bottom side, ie with the ambient pressure of 1 bar absolute. For air springs, there are several versions of the damper bearing:

• 1) completely outside the pressure chamber, ie in the environment,
• 2) completely inside the pressure chamber and
• 3) at the separation point between the working space (pressure chamber) and the environment.

A fully out of the pressure chamber arranged damper bearing is - as in the steel spring design - acted on the top and bottom with the ambient pressure. This implies the advantage that no pressure surges act on the damper bearing, which could lead to movements of the piston rod. Due to the position outside the pressure chamber, the piston rod must be guided to the outside and sealed. However, it moves by wheel forces relative to the strut by several millimeters in the axial direction. In addition, significant transverse and angular movements occur, which is why the seal is expensive and therefore expensive. If a damper valve is provided in this embodiment, its connection cable can be guided via the piston rod to the outside. Such air spring module is for example from the EP 1 402 195 B1 known.

As a further embodiment, the damper bearing can be completely provided within the pressure chamber. However, this embodiment is only applicable if the damper adjustment is arranged outside of the damper, since with a damper valve in the damper piston, the connection cable must be guided by the piston rod to the outside. To seal this cable and all its strands is very expensive and therefore economically very disadvantageous. Therefore, this design is usually applied only when no cable must be led to the outside.

The third embodiment, in which the damper bearing is acted upon on the one hand with the ambient pressure and on the other hand with the air spring pressure, made possible by the arrangement at the separation point between the pressure chamber and the environment, the cable of the damper valve in the damper piston without expensive, expensive seal to the outside. A disadvantage of this embodiment, however, is that the top of the damper bearing is exposed to the constant ambient pressure and the bottom of the air spring pressure. Thus, pressure surges are not compensated, which leads to movements of the damper bearing. These are transmitted to the piston rod and thus lead to an uncomfortable driving behavior.

To keep their effects as low as possible, is in the generic DE 102 29 287 A1 the damper bearing made in two parts. The two-piece damper bearing has according to the DE 102 29 287 A1 a conventional damper bearing with a large pressure surface for receiving large piston rod axial forces and an additional radial damper bearing with a small pressure surface, the large pressure surface is completely outside the pressure chamber and the pressure surges that occur, these act only on a relatively smaller area of additional damper bearing, which also smaller forces and thus smaller piston rod movements are induced. The additional damper bearing with the small pressure application surface has a small and a large sleeve, which are connected by means of vulcanized rubber. The rubber is claimed in piston rod movements to shear, which is why the additional damper bearing is also called thrust bearing, which can transmit only low axial forces.

The damper bearing is designed so that the force-displacement curve leads to optimal piston rod movements and thus optimum ride comfort.

The third embodiment has the disadvantage that the arrangement builds axially relatively long. As a result, valuable travel can be lost or use due to limited installation space from the outset impossible. Another disadvantage is the large number of items, which leads to higher costs, both from the parts manufacturing ago, as required by the assembly effort.

It is also disadvantageous that due to the long axial extent a relatively indefinite pivot point and large paths and deformations occur during angular movement (gimbals), which in turn is unfavorable for the life and the lowest possible cardan rigidity.

The invention is therefore based on the object to provide an improved air spring module with a damper bearing at the interface between the environment and the pressure chamber.

The object is achieved in that the damper bearing arranged in the lid, sealed outer ring having a radially inwardly facing, circumferential projection and arranged on the piston rod inner ring, which are connected by means of an elastomeric ring, wherein the circumferential projection on both sides is surrounded by a metal disc connected to the piston rod with the interposition of an elastic member. Due to the inventive design of the damper bearing, the overall length can be significantly shortened and the assembly costs are reduced. Furthermore, the unfavorable pivot point for all components can be avoided and thus a low gimbal rigidity and a longer service life can be achieved.

According to an advantageous embodiment of the invention, the outer ring is fixed in a cup-shaped portion of the lid, which extends in the direction of working space, sealed. Thus, the damper bearing can be easily mounted in the lid and fixed by means of simple attachment methods.

A simple and secure sealing of the damper bearing to the cover can be achieved according to an advantageous development of the invention in that the outer ring has a circumferential outer groove, in which an annular seal can be arranged to seal the lid.

An alternative embodiment provides that the outer ring has a circumferential outer groove, in which a circumferential sealing lip is provided vulcanized to seal the lid. Thus, an additional assembly of a sealing element can be omitted.

A simple and secure sealing of the damper bearing to the piston rod can be achieved according to an advantageous embodiment of the invention in that the piston rod has a circumferential outer groove, in which an annular seal can be arranged to seal the inner ring.

According to an advantageous development, arranged between the circumferential projection and metal discs, elastic components are provided as highly flexible polyurethane discs. Due to the open-pore polyurethane, the air can spread on both sides of the metal discs, so that no pressure difference arises even with pressure surges and no forces are induced on the piston rod.

A further advantageous embodiment of the invention provides that the arranged between the circumferential projection and metal discs, elastic components are provided as vulcanized to the metal discs and / or the protrusion rubber studs. The assembly of the two elastic components could thus be omitted.

According to another advantageous embodiment of the invention, arranged between the circumferential projection and metal discs, elastic member are integrally provided with the elastomeric ring. The advantage of this is that the components can be manufactured and assembled in one step.

Preferably, the metal discs to accelerate the pressure equalization on one or more holes. Alternatively, to accelerate the pressure compensation, the metal disks can have a plurality of radially arranged channels on the sides facing the elastic component. Both embodiments have the advantage that the air spreads very quickly on the metal discs and a power transmission is excluded on the piston rod.

The length of the air spring module can be further reduced by the air spring facing away from the metal disc has a recess for sinking a fastening nut for the piston rod.

A shortening of the overall length and a simultaneous reduction of the components can preferably be achieved in that the metal disc facing away from the air spring is provided as a fastening nut for the piston rod.

Are the inner ring according to an advantageous embodiment of the invention concave and the projection on its inside convex provided, angular movements of the air spring or the air spring module can be facilitated.

To facilitate the angular movement of the circumferential projection according to a further embodiment of the invention may have a substantially spherical cross-section with a radially inwardly increasing thickness, wherein the metal discs are each formed increasingly strong in corresponding shape on the side facing the elastic member.

Preferably, the inner ring and the air spring facing metal disc can be integrally provided, whereby the assembly and the number of components can be further improved.

According to a further advantageous embodiment of the invention, the outer ring can also be provided reduced to the radial, circumferential projection and secured in a circumferential groove of the cup-shaped portion of the lid.

Other features, advantages and applications of the invention will become apparent from the dependent claims and the following description of exemplary embodiments and with reference to the drawings. It shows highly schematized as well as on average:

1 a first embodiment of an air spring module with damper bearing according to the invention;

2 a section of the air spring module according to 1

3 a detail of a second embodiment according to the invention of an air spring module with damper bearing;

4a a detail of a third embodiment of an air spring module with damper bearing according to the invention;

4b a plan view of a section of the air spring module according to 4a along the line AA;

5a a detail of a fourth embodiment of an air spring module with damper bearing according to the invention;

5b a plan view of a section of the air spring module according to 5a along the line AA;

5c a plan view of a section of the air spring module according to 5b along the line BB;

6 a detail of a fifth embodiment of an air spring module with damper bearing according to the invention;

7 a detail of a sixth embodiment of an air spring module with damper bearing according to the invention;

8th a detail of a seventh embodiment of an air spring module with damper bearing according to the invention;

9 a detail of an eighth embodiment of an air spring module with damper bearing according to the invention;

10 a section of a ninth embodiment of an air spring module with damper bearing according to the invention;

11 a section of a tenth embodiment of an air spring module with damper bearing and according to the invention

12 a detail of an eleventh embodiment of an air spring module with damper bearing according to the invention.

1 shows an air spring module 1 consisting of an air spring 2 and a shock absorber 3 for suspension and damping of vibrations of a motor vehicle chassis, which is fastened in the motor vehicle preferably at a first end fixed to the body and at a second end to a wheel suspension. The air spring 2 consists of a body-tight cover 4 , airtight with a clamping ring 5 fastened first end of a rolling bellows 6 , which is a filled with compressed air working or pressure chamber 7 at least partially limited. A second end of the rolling bellows 6 is airtight with a rolling piston 8th connected. The rolling piston 8th on which the rolling bellows 6 Can roll over an O-ring 9 airtight with a cylinder tube 10 of the shock absorber 3 connected to the cylinder tube 10 preferably the damper fork attachable to the suspension 11 is attached. A second end of the cylinder tube 10 has an end face a bore for a piston rod 13 of the shock absorber 3 on, with almost complete deflection of the air spring module, the end face of the cylinder tube 10 on an additional spring 14 supports, concentric to a piston rod 13 of the shock absorber 3 is arranged. The additional spring 14 will be in a leadership ring 15 guided. This guide ring 15 can with the lid 4 firmly connected or with the lid 4 be provided in one piece.

An outdoor tour 12 can with a first end to the rolling bellows 6 by means of a clamping ring or - as in 1 is shown - on the lid 4 be attached.

For sealing the working space 7 is a damper bearing 16 provided, which is the piston rod 13 with the vehicle-mounted cover 4 the air spring 2 connects, with the damper bearing 16 in the lid 4 arranged and acted on the one hand with the ambient pressure and on the other hand with the air spring pressure.

By the arrangement at the separation point between working space 7 and environment, can be a connection cable 17 a damper valve in the piston rod 13 be carried out without expensive, expensive seal to the outside.

In order to avoid the described disadvantages of known damper bearings arranged at the point of separation between the pressure chamber and the surroundings, the damper bearings shown and described in detail below 16 the individual embodiments one in the lid 4 arranged, sealed outer ring 18 with a radially inwardly facing, circumferential projection 19 and one on the piston rod 13 arranged, sleeve-shaped inner ring 20 on. The circumferential projection 19 of the outer ring 18 and the inner ring 20 are by means of an elastomeric ring 21 connected, with the circumferential projection 19 on both sides of one with the piston rod 13 connected metal disc 22 . 23 with the interposition of an elastic component 24 . 25 is surrounded.

This embodiment of the damper bearing 16 prevents a large length and a high installation cost of the air spring module according to the invention 1 , Furthermore, the unfavorable pivot point for all components is avoided and thus enables a low gimbal rigidity and a longer service life.

2 now shows the damper bearing 16 of in 1 shown first embodiment in an enlarged view. As can be seen, the outer ring 18 in a cup-shaped section 26 of the lid 4 , which is towards the working space 7 extends, sealed fixed. The damper bearing 16 can easily in the lid 4 mounted and fixed by means of simple attachment methods. For example, it is possible as in 2 shown, ends of the cup-shaped portion 26 reshape the outer ring 18 sure to fix.

In the context of the invention, however, further known mounting options are conceivable.

For sealing the damper bearing 16 against the cup-shaped section 26 of the lid 4 the outer ring has a centrally located, circumferential outer groove, in which an annular seal in the form of an O-ring 28 is arranged. The seal to the piston rod 13 done by a on the piston rod 13 arranged, circumferential outer groove 29 in which an annular seal in the form of an O-ring 30 is inserted.

The air spring 2 remote metal disc 22 acts as a pull pulley, which is outside the working space 7 located. The air spring 2 facing metal disc 23 In contrast, absorbs the pressure forces on the air suspension module and is on both sides with the pressure of the working space 7 applied.

How out 2 clearly seen, the elastomeric ring extends 21 which is advantageously made of rubber, over an entire outer surface of the inner ring 20 and also over an entire inner surface of the projection 19 , That between the circumferential projection 19 and the metal discs 22 . 23 arranged, elastic member is provided as a highly flexible polyurethane disc, which is made for example of the known material Cellasto ^® .

Through the open-pored polyurethane, the air can on both sides of the metal discs 22 . 23 spread, so that no pressure differences arise even with pressure surges or pressure fluctuations and no forces on the piston rod 13 be induced.

One on the piston rod 13 screwed fixing nut 31 fixes the piston rod 13 in the damper bearing 16 , wherein the air spring facing metal disc 23 on a heel 32 the piston rod 13 is applied.

The exemplary embodiments described below are essentially like that according to FIGS 1 and 2 constructed air spring module, so that is dispensed with a repeated description and will only address the differences according to the invention.

The in 3 shown, enlarged portion of a second embodiment differs from the first embodiment in that instead of an O-ring for sealing the damper bearing 16 to the lid 4 one in a circumferential outer groove 33 vulcanized, circumferential sealing lip 34 is provided, whereby the additional assembly O-ring can be omitted. The circumferential outer groove 33 is preferably on one of the air spring 2 facing the end of the outer ring 18 arranged.

To accelerate the pressure compensation on the metal discs 22 . 23 , have these according to the in the 4a and 4b illustrated embodiment, one or more holes 35 . 36 on.

Alternatively, the metal discs 22 . 23 to accelerate the pressure equalization according to the in 5a C illustrated embodiment of the elastic member 24 . 25 facing side a plurality of radially disposed channels 37 exhibit. Both embodiments have the advantage that the air very quickly on the metal discs 22 . 23 spreads and a power transmission to the piston rod 13 is excluded.

6 shows a fifth embodiment, in which the inner ring 20 concave and the projection 19 are provided convex on its inner side, so that angular movements, ie the Kardanik the air spring or the air spring module can be facilitated.

Alternatively shows 7 in a sixth embodiment to facilitate the angular movement of a substantially spherical cross-section of the projection 19 with a radially inward increasing thickness. The metal discs 22 . 23 are in appropriate shape of the elastic member 24 . 25 facing each increasingly increasingly strong, thereby also the elastic components 24 . 25 to the shape of the other components 19 . 22 . 23 are adjusted.

According to the in 8th illustrated embodiment, the length of the air spring module 1 be further reduced by the air spring 2 remote metal disc 22 a recess 38 for sinking a fastening nut 31 having. The metal disc 22 is then, as in 8th can be seen, formed cranked.

In contrast, a shortening of the overall length and at the same time a reduction of the components according to the in 9 shown embodiment can be achieved in that the air spring facing away from the metal disc 22 as a fastening nut for the piston rod 13 is provided and on the piston rod 13 is screwed on.

An in 10 shown embodiment provides that between the circumferential projection 19 and the metal discs 22 . 23 arranged, elastic components 24 . 25 as to the metal discs 22 . 23 and / or the lead 19 vulcanized rubber knobs are provided. The assembly of the two elastic components could thus be omitted. Alternatively, the rubber studs can also be attached to the outer ring 18 vulcanized.

As 11 can be seen, which shows a tenth embodiment, the elastic components 24 . 25 one-piece with the elastomer ring 21 be provided. The material is at the projection 19 vulcanized so that from the projection 19 made of rubber studs in the direction of the metal discs 22 . 23 extend.

12 shows a section of an eleventh embodiment, in which the inner ring 18 and the air spring 2 facing metal disc 23 provided in one piece. As a result, the assembly and the number of components can be further improved. At the same time, this embodiment already has the 9 shown as a fastening nut serving, cranked metal disc 22 ,

The outer ring 18 is on the radial, circumferential projection 19 provided reduced and in a circumferential groove 39 the cup-shaped section 26 of the lid 4 attached.

LIST OF REFERENCE NUMBERS

1

Leveling Module

2

air spring

3

shock absorber

4

cover

5

clamping ring

6

bellows

7

working space

8th

roll-off

9

O-ring

10

cylinder tube

11

Shock fork

12

external guide

13

piston rod

14

additional spring

15

guide ring

16

top mounts

17

Connection Cable

18

outer ring

19

head Start

20

inner ring

21

Elastomeric ring

22

metal disc

23

metal disc

24

Elastic component

25

Elastic component

26

Pot-shaped section

27

outer groove

28

poetry

29

outer groove

30

poetry

31

fixing nut

32

paragraph

33

outer groove

34

sealing lip

35

drilling

36

drilling

37

channel

38

recess

39

groove

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

• EP 1402195 B1 [0003]
• DE 10229287 A1 [0006, 0006]

Claims (16)

Air spring module ( 1 ) consisting of an air spring ( 2 ) and a shock absorber ( 3 ) for suspension and damping of vibrations of a motor vehicle chassis, with - a cover ( 4 ) and - an attached airtight rolling bellows ( 6 ), which a working space filled with compressed air ( 7 ) at least partially limited, - a rolling piston ( 8th ), which on a cylinder tube ( 10 ) of the shock absorber ( 3 ) and on which the rolling bellows ( 6 ) rolls, - one to seal the working space ( 7 ) provided damper bearing ( 16 ), which is a piston rod ( 13 ) of the shock absorber ( 3 ) with the lid ( 4 ), wherein the damper bearing ( 16 ) in the lid ( 4 ) is arranged and on the one hand with the ambient pressure and on the other hand acted upon by the air spring pressure, - an additional spring ( 14 ) concentric with the piston rod ( 13 ) is arranged and in a guide ring ( 15 ), which with the lid ( 4 ) or with the lid ( 4 ) is provided in one piece, - wherein the cylinder tube ( 10 ) of the shock absorber ( 3 ) at a first end via a damper fork ( 11 ) is attached to a suspension and at a second end on an end face a bore for the piston rod ( 13 ), with almost complete deflection of the air spring module ( 1 ) the end face of the cylinder tube ( 10 ) on the auxiliary spring ( 14 ), characterized in that the damper bearing ( 16 ) one in the lid ( 4 ), sealed outer ring ( 18 ) with a radially inwardly facing, circumferential projection ( 19 ) and one on the piston rod ( 13 ) arranged inner ring ( 20 ), which by means of an elastomeric ring ( 21 ), wherein the circumferential projection ( 19 ) on both sides of one with the piston rod ( 13 ) connected metal disc ( 22 . 23 ) with the interposition of an elastic component ( 24 . 25 ) is surrounded. Air spring module ( 1 ) according to claim 1, characterized in that the outer ring ( 18 ) in a pot-shaped section ( 26 ) of the lid ( 4 ), which moves in the direction of the working space ( 7 ), sealed is fixed. Air spring module according to claim 2, characterized in that the outer ring ( 18 ) a circumferential outer groove ( 27 ), in which for sealing to the lid ( 4 ) an annular seal ( 28 ) can be arranged. Air spring module ( 1 ) according to claim 2, characterized in that the outer ring ( 18 ) a circumferential outer groove ( 33 ), in which for sealing to the lid ( 4 ) a circumferential sealing lip ( 34 ) vulcanized is provided. Air spring module ( 1 ) according to one of the preceding claims, characterized in that the piston rod ( 13 ) a circumferential outer groove ( 29 ), in which for sealing to the inner ring ( 20 ) an annular seal ( 30 ) can be arranged. Air spring module ( 1 ) according to one of the preceding claims, characterized in that the between circumferential projection ( 19 ) and metal discs ( 22 . 23 ), elastic components ( 24 . 25 ) are provided as highly flexible polyurethane discs. Air spring module ( 1 ) according to one of the preceding claims 1 to 5, characterized in that between the circumferential projection ( 19 ) and metal discs ( 22 . 23 ), elastic component ( 24 . 25 ) than to the metal discs ( 22 . 23 ) and / or the lead ( 29 ) Vulcanized rubber knobs are provided. Air spring module ( 1 ) according to one of the preceding claims 1 to 5, characterized in that between the circumferential projection ( 19 ) and metal discs ( 22 . 23 ), elastic components ( 24 . 25 ) in one piece with the elastomer ring ( 21 ) are provided. Air spring module ( 1 ) according to one of the preceding claims, characterized in that the metal discs ( 22 . 23 ) to accelerate the pressure equalization one or more holes ( 35 . 36 ) exhibit. Air spring module ( 1 ) according to one of the preceding claims 1 to 8, characterized in that the metal discs ( 22 . 23 ) to accelerate the pressure equalization on the elastic component ( 24 . 25 ) facing sides a plurality of radially disposed channels ( 37 ) exhibit. Air spring module ( 1 ) according to one of the preceding claims, characterized in that the air spring ( 2 ) facing away from metal disc ( 22 ) a recess ( 38 ) for sinking a fastening nut ( 31 ) for the piston rod ( 13 ) having. Air spring module ( 1 ) according to one of the preceding claims 1 to 10, characterized in that the air spring ( 2 ) facing away from metal disc ( 22 ) as a fastening nut for the piston rod ( 13 ) is provided. Air spring module ( 1 ) according to one of the preceding claims, characterized that the inner ring ( 20 ) is concave and the projection ( 19 ) is provided convexly on its inside. Air spring module ( 1 ) according to one of the preceding claims 1 to 12, characterized in that the circumferential projection ( 19 ) has a substantially spherical cross-section with a radially inwardly increasing thickness, wherein the metal discs ( 22 . 23 ) in a corresponding shape on the elastic component ( 24 . 25 ) facing side are each increasingly increasingly strong. Air spring module ( 1 ) according to one of the preceding claims, characterized in that the inner ring ( 20 ) and the air spring ( 2 ) facing metal disc ( 23 ) are provided in one piece. Air spring module ( 1 ) according to one of the preceding claims, characterized in that the outer ring ( 18 ) on the radial, circumferential projection ( 19 ) reduced and provided in a circumferential groove ( 39 ) of the cup-shaped section ( 26 ) of the lid ( 4 ) is attached.

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