WO2016078656A1

WO2016078656A1 - Elastomer coupling and associated roll stabilizer

Info

Publication number: WO2016078656A1
Application number: PCT/DE2015/200491
Authority: WO
Inventors: Reiner Voss; Jochen Rosenfeld; Markus Holzberger
Original assignee: Schaeffler Technologies AG & Co. KG
Priority date: 2014-11-20
Filing date: 2015-11-04
Publication date: 2016-05-26
Also published as: DE102014223706A1

Abstract

The invention relates to an elastomer coupling (10) for an electromechanical actuator, comprising an input part and an output part, wherein either the input part or the output part has a plurality of webs that are arranged in such a way that the webs are distributed around an axis of rotation and that extend radially outwardly and the other part has webs that are arranged on the inside of a hollow body and extend radially inwardly, wherein the radially inwardly extending and the radially outwardly extending webs (13, 14) mesh with each other and form pockets for elastic shaped elements (7), wherein a shaped element (7) has two materials of different elasticity.

Description

Elastomer coupling and associated roll stabilizer

The invention relates to an elastomer coupling for an electromechanical actuator, comprising a lifting part and a driven part, wherein either the driving part or the driven part has a plurality of webs distributed around a rotation axis extending radially outwards and the respective other part on the inside of a hollow body arranged, radially inwardly extending webs, wherein the radially inwardly and radially outwardly extending webs engage with each other and form pockets for elastic molded body

An elastomer coupling is part of a roll stabilizer for a motor vehicle, wherein an active roll stabilizer can be installed on a front axle and / or on a rear axle of a motor vehicle. An electromechanical roll stabilizer comprises an electric motor, a control unit, a multi-stage planetary gear and an elastomer coupling, the stock of an eggastomer decoupling unit (EKE) and the actuator z. B, decoupled from influences due to road bumps when driving straight ahead. Small rotations between torsion bars are absorbed by moldings made of an elastomer,

A roll stabilizer with an elastomer coupling is known from EP 2 213 489 A1. A drive part is designed as an inner star and a Abtriebsteii is formed as an outer star, between the inner and outer, intermeshing webs each one made of an elastomer molded body is added. This results in a certain, desired course of the torque over the

Angle of rotation between Antriebstei! and output shaft or between the two rotating rods of the roll stabilizer. The active roll stabilizer has a high elasticity for small torques or torques. There are relative movements between the Antriebstei! and the driven part with deformation of the molded body without transmission of a significant torque possible. From a certain angle of rotation, however, the transmitted torque increases progressively. Upon further deformation of the molded bodies, a progressive increase in stiffness occurs. Thus, small rotations of the Orehstäbe of the stabilizer z. 8 by lane Unevenness occurs, are absorbed by the moldings, whereby the ride comfort is increased. When cornering and possibly also with different road bumps between the right and the left side can be reduced by active rotation of the two stabilizer halves mitteis the roll stabilizer, the rolling motion of the vehicle.

Figures 1-3 show components of one developed by the applicants

Elastomer coupling. FIG. 1 shows a drive part 1 with an inner star 2, whose webs 3 have molded bodies 4, 5 vulcanized on both soaps. FIG. 2 shows a driven part 6 designed as an outer star, which has recesses adapted to the inner star 2 and shaped in the same shape. Between the inner star 2 and the outer star clearances are formed which allow a deformation of the shaped bodies 4, 5 in the case of touch, in the mounted state, the inner star is inserted into the outer star, whereby the elastomer coupling is formed, which is used to transmit a Torsionsmoments suitable is

FIG. 3 is an enlarged, sectional view of a web 2 of the inner star shown in FIG. The z. B. made of a steel alloy web 2 has on both sides of the vulcanized molded body 4; 5 on. Up to a certain

Wankwinke! The elastomer coupling behaves softly, that is, the slope of the stiffness characteristic is low When reaching a critical angle of the molded body made of the elastomer is completely absorbed in a recess between the inner star and the outer star and thus behaves incompressible. When this limit angle is exceeded, the elastomer coupling behaves stiffly, that is, the stiffness characteristic curve has a large pitch. This bilinear behavior of the elastomer clutch reduces the number of required control interventions, in particular when driving on bad carriageways

Wankstabilisators, Thus, the drive motor of the roll stabilizer is decoupled due to the soft characteristic of the elastomeric clutch in such road conditions quasi quasi movements of the torsion bars.

The functional principle of this known elastomer coupling is based on the fact that the vulcanized material vulcanised onto the thin star! assumes the function of a spring, which under torsional load is predominantly pressurized At high torques to be transmitted, however, such a conventional elastomer coupling reaches its limit, since the strength of the elastomer material used is exceeded at a certain torque. The conventional elastomer coupling can thus not be readily designed for higher torques to be transmitted, especially since the available space is limited.

The invention is therefore based on the object to provide an elastomeric coupling, which is also suitable for a high torque to be transmitted.

In order to achieve this object, it is provided according to the invention in an elastomer coupling of the aforementioned type that a shaped body has two materials of different elasticity

According to the invention, a modified shaped body is used, which does not consist merely of an elastomer, but in addition to an elastomer, a second material with a different elasticity is used. The shaped bodies comprising the two materials of different elasticity can also be used at a higher torque occurring

According to the invention, it is preferred that at least one material is a foam. The material thus has pores. which are filled with air or a gas. Preferably, the foam of the elastomeric coupling according to the invention

closed-cell, so that the gas trapped in the pores is compressible. This compressibility results in the desired elastic behavior, so that at a low torque occurring this is absorbed by elastic deformation of the shaped body and compression of the gas enclosed in the pores or lines. Only when the limit value for the torque is exceeded and when the limit angle is exceeded, a rotation of the driven part takes place

In the context of the invention it can also be provided that at least one material is polyurethane or a polyurethane compound or polyurethane or a Polyurethane compound comprises, Such a molded body can be manufactured by the Spritzgussverfah- ren.

It is also within the scope of the invention that at least one material is an elastomer or a thermoplastic elastomer (TPE). Accordingly, the molded body preferably has a foam as the first material and an elastomer or a thermoplastic elastomer as the second material.

In the context of the invention, it is particularly preferred that the material having the lower eggastt is surrounded by the material having the greater elasticity. The material having the lower elasticity is soft, that is to say with an existing torque, the soft material having a low rigidity is first of all deformed, in particular compressed. Only when no further compression is possible, the second material, which has the greater elasticity, is compressed. As soon as the second material, which surrounds the first material, is completely compressed, the torque is transmitted from the drive part to the driven part or in the opposite direction. If the material having the low elasticity is surrounded by the material having the greater elasticity, the material arranged on the inside is protected since, in particular if it is a foam, it has lower mechanical properties, in particular a lower modulus of elasticity and a lower elasticity lower pressure resistance. A further advantage is the fact that no particles or the like can penetrate into other regions of the elastomer coupling or the roll stabilizer even if the internally arranged material is damaged. However, in principle, an opposite structure is also possible, in which the material having the lower elasticity is possible surrounds the material having the greater elasticity.

In order to simplify the production of the elastomer coupling according to the invention, it is preferred that the elastic shaped bodies consisting of the two materials and arranged in the pockets have an integral construction! In the assembled state, the integral component is inserted into clearances between the driven part and the drive part. Since the shaped bodies forming the integral components are located between the radially inwardly and radially outwardly directed webs, the integra- component has a cylindrical basic shape and a meandering annular cross section or the shape of a rosette,

In the case of the elastomer coupling according to the invention, the pockets are designed such that free spaces are provided in the pockets, which allow elastic deformation of the molded bodies. Accordingly, the integral component is in the unloaded state, that is, when no torque is present. Not everywhere on corresponding surfaces of the webs, but there are free spaces partially between the integral component and the webs available that allow deformation of the first material and the second material. With increasing load, these free spaces disappear because the first material and the second material are elastically deformed; this deformation or the filling in of the free spaces is also referred to as chambering. In addition, the invention relates to a roll stabilizer, which is connectable or connected to the torsion bars of a split stabilizer and having a eiektromechanischen actuator with a drive part and a driven part. The roll stabilizer according to the invention is distinguished by the fact that between the drive shaft! and the output member an elastomeric clutch of the type described is arranged.

Further advantages and details of the invention will be explained below with reference to exemplary embodiments with reference to the drawings. The drawings are schematic representations and show:

Figure 1 is a perspective view of a drive part with an outer star of a conventional elastomeric coupling;

Figure 2 is a perspective view of a Abtnebsteils with an inner star of a conventional elastomeric coupling;

Figure 3 is a sectional view of the outer star shown in Figure 1;

FIG. 4 shows a perspective view of an integral component formed from elastic shaped bodies; FIG. 5 an axial view of the essential components of an elastomer coupling according to the invention;

FIG. 6 shows the elastomer coupling tn shown in FIG. 5 in a perspective view; and

7 shows an enlarged detail of the Eistornerkupplung of Figure 5

FIG. 4 is a perspective view showing an elastic molded body 7 which is injection-molded and which, when assembled, is shown in FIG

Elastomeric coupling between a Antriebsteii and a Abträebsteil is,

The molded body 7 has a cylindrical basic shape and a meandering cross section. The molded body 7 consists of two materials of different elasticity, the material arranged in the interior of the molded body 7 is a

Closed-cell foam 8 made of polyurethane, which is surrounded by a second material. In this embodiment, the second, outer material is a thermoplastic elastomer 9 (TPE). The molded body 7 is made as a one-piece, integral component, so that even a failure of the foam 8 received in the interior of the molded body 7 does not release any particles. FIG. 4 shows that the foam 8 extends in the longitudinal direction of the molded body 7 and has a curved shape. The foam 8 is completely surrounded by the thermoplastic elastomer 9. Naturally, the closed-cell foam 8 has a lower elasticity, that is a lower modulus of elasticity than the thermoplastic elastomer. On the other hand, the foam 8 is due to its cells or pores, which are air or gas are filled, compressible, so that its volume is reduced at an applied pressure. This volume change is elastic _; that is, when the pressure, which can also be generated by an attacking torque, no longer acts, the foam 8 returns elastically to its original position.

FIG. 5 is an axial view of an elastomeric coupling 10 for an electromechanical actuator (not shown) of a roll stabilizer. The elastomer coupling holds a drive stiffener and an output part, the drive part is formed in this embodiment example as inner star 11, which is connected at its opposite side with a Planetentrager. The planet carrier 12 partially shown in the perspective view of FIG. 6 is connected to an electric drive motor via further stages of a planetary gear. Upon rotation of the electric drive motor, the inner star 11 is thus rotated. The inner star 11 comprises webs 13 extending in the radial direction.

In FIG. 5 it can be seen that the inner star 1 1 is surrounded by an outer star 15 having a web 14, wherein the radially outwardly pointing webs 13 of the inner star 11 and the radially inwardly pointing webs 14 of the outer star 15 engage with one another. In each case, pockets are formed between the webs 13, 14. It is also shown in FIG. 5 that a free space is provided between the outer ends of the webs 13 and the outer window 15, that is, the webs 13 are provided by an inner surface of the web Outer star 15 spaced. The molded body 7 is inserted between the inner star 1 1 and the outer star 15, wherein the shaped body 11 is shaped such that the one hand is adapted to the outer contour of the inner star 11 and on the other hand to the inner contour of the outer star 15 those areas of the molded body 7, in which the foam 8 is located, are arranged so that they are parallel to the axial direction next to a web 13. The areas of the molded body 7 which have the foam 8 are thus in each case located between a web 13 and a web 14. in the enlarged view of FIG. 7 it can be seen that the molded body 7 does not abut the surfaces of the inner star 1 1 everywhere. Rather, free spaces 16 are formed between the outer side of the web 13 and the molded body 7, as well as free spaces 17 in the region of the free end of the webs 14 and free spaces 18 in the foot region of the webs 14. These free spaces 16, 17, 18 are cavities, which are filled in an elastic deformation of the molding 7 of this.

The molded body 7 is designed so that it has a nonlinear stiffness characteristic. At low load, that is, at a low torque and a low angle of rotation, the molded body 7 behaves soft, from a certain

Limit angle increases the rigidity progressively, so that the shaped body 7 like a ne stiff spring behavior. This arrest is desired, since in this way low acting torques _: the z. B. caused by road bumps and introduced via torsion springs of the stabilizer in the roll bar, can be absorbed by elastic deformation of the molding 7. Thus, no transmission of the torque from the Antriebstei! on the driven part or in the opposite direction. Accordingly, the undesirable copying effect that occurs in a rigid coupling is avoided. Only with a higher attacking torque, which is generated, for example, by the activated electromechanical actuator, does no further elastic deformation of the shaped body 7 become possible, so that the rotating drive element! the output part rotates.

A low attacking torque can be absorbed by elastic deformation of the molded body 7, in which case the foam 8 located in the interior of the molded body 7 is first compressed, since this has a lower elasticity. Accordingly, the foam 8 enclosed between two webs 13, 14 is compressed; this process takes place on all of the webs, that is to say in the illustrated exemplary embodiment on five webs until no further compression of the foam 8 is possible with a further increasing load The molded body 7 is thereby compressed so that in the unloaded state existing free spaces 16, 17, 18 between a web 13 and a web 14 gradually from the deformed shaped body. 7 fill out. In this condition, no further elastic absorption of energy is possible; from this point in time the applied torque causes a rotation of the drive member. When loaded in the reverse direction, an adjacent portion of the molded body 7 is acted upon.

The elastomer coupling 10 described is able to absorb higher torques than a conventional elastomer coupling with an unchanged installation space, since the compressible material, in this case the foam 8, is completely received in the interior of the molded body 7 and thus protected against damage. LIST OF REFERENCE NUMBERS

1 drive part

2 inner stars

3 footbridge

4 moldings

5 moldings

6 output part

7 moldings

8 foam

9 elastomer

10 elastomer coupling

1 1 star

12 planet carriers

13 footbridge

14 footbridge

15 outer star

16 free space

17 free space

18 free space

Claims

Fatentansprüche

1 elastomeric coupling (10) for a eiektromechanischen actuator, with a drive part and a driven part, wherein either the drive part or the driven part a plurality of distributed around an axis of rotation arranged radially outwardly extending webs (13) and the respective other part of the Inner side of a hollow body arranged, radially inwardly extending webs (14), wherein the radially inwardly and radially outwardly extending webs (13,14) engage with each other and pockets for elastic molded body (?) Form, characterized in that a shaped body (7) has two materials of different elasticity

2. Elastomer coupling according to claim 1 _: characterized in that at least one material is a foam (8).

3. elastomeric coupling according to claim 2, characterized in that the

Foam (8) is closed cell.

4. elastomeric coupling according to one of the preceding claims, character- ized in that at least one material polyurethane or a

Polyurethane compound or polyurethane or a polyurethane compound.

5. Elastomer coupling according to one of the preceding claims, character- ized in that at least one material is an elastomer or a thermoplastic elastomer (IRE).

6. Elastomer coupling according to one of the preceding claims, character- ized in that the lower elasticity having material is surrounded by the material having the greater elasticity.

7. elastomer coupling according to one of the preceding claims, character- ized in that the existing of the two materials, arranged in the pockets elastic molded body (7) biäden an integral Bauteii. Elastomer coupling according to one of the preceding claims, characterized in that an elastic deformation of the shaped bodies (7) enabling free spaces (16, 17, 18} are present in the pockets.

Roll stabilizer, which is connectable or connected to torsion bars of a divided stabilizer and has an electromechanical actuator with a drive part and a driven part, between which a

Elastomer coupling (10) is arranged according to one of claims 1 to 8