DE102021118280A1 - Elastomer-metal bearing and method for its manufacture - Google Patents

Abstract

The invention relates to an elastomer-metal bearing (1) with an inner sleeve (2) and an element (3) made of elastic material on its outer diameter (2.2), the elastic element (3) being made of TPE (thermoplastic elastomer) according to the invention. to form a TPE metal bearing and a method of making the same.

Description

The invention relates to an elastomer-metal bearing according to the preamble of the first claim and a method for its manufacture.

In the chassis, rubber-metal components play an important role as elastokinematic connecting elements in the transmission of influences that can be assigned to the NVH (Noise, Vibration and Harshness - includes acoustic and mechanical vibrations and their subjective perceptions by humans) area. "Bernd Heissing, Metin Ersoy Springer Verlag 2008 chassis manual pages 421 - 422". It also states that the elastomeric chassis mounts not only influence the dynamic transmission properties of all chassis components, but are also used as vibroacoustic tuning elements for the psychoacoustic and driving dynamics specifications of the vehicle manufacturers in order to achieve the development goals such as an unmistakable sound characteristic of the drive, high driving safety and sportiness and achieve agility. The quasi-static and dynamic transmission properties of the chassis mounts are essentially determined by the material properties and the component geometry. The material parameters of the elastomeric materials show a significant dependency on the type of excitation, the influence of the environment (temperature, prestress, chemical reactions with environmental media) and the load history (ageing, settlement, pre-deformation, overload and misuse). The elastomer materials are now developed and produced according to the technical requirements for the respective installation positions of the chassis bearings. In contrast to metallic materials, elastomeric materials have hyperelastic and inherent damping properties that are used constructively for vibration and noise isolation. Nevertheless, the damping capacity of the rubber materials is not sufficient for every vibration isolation in the chassis.

In the case of conventional sealing bellows and rubber-metal mounts (GMT) for chassis components such as chassis links and struts, the elastic component is currently made of a material that can be classified in the group of elastomers. This is commonly referred to as gum. The elastic properties of this group of materials are necessary for the functional fulfillment of the components. However, rubber is processed exclusively by vulcanization, which means a high expenditure of energy and time.

Known elastomer-metal bearings or rubber-metal bearings have an outer and an inner metal sleeve and a rubber body arranged in between. In some known generic bearings, an outer sleeve is also dispensed with and the inner sleeve with a rubber body seated on it is inserted into a bore.

A generic elastomer-metal bearing, which has an inner part, an elastomeric body - referred to as an elastomeric sleeve - and an outer part is from DE 10 2010 037 891 A1 known. In this case, the elastomeric sleeve is arranged between the inner part and the outer part and the inner part is designed on at least one axial end section in such a way that it forms a form fit with an adjoining component that can be connected to the inner part with respect to a force transmission transverse to a bearing axis defined by the inner part. For this purpose at least one axial end section of the inner part is conical, the inner part is designed as a metallic sleeve which is surrounded by the elastomeric sleeve in an adhesive manner and the inner part protrudes with its conical end section from the elastomeric sleeve. The elastomeric sleeve is vulcanized to the inner or outer part and consists of a suitably elastic rubber.

In the pamphlet DE 32 40 981 A1 describes a generic rubber-metal bearing for rear axle constructions of motor vehicles with separate transverse and longitudinal guidance, the lateral surface of the inner metal sleeve having surface sections offset from one another in the circumferential direction, each of which rises to one of the two end faces. These surface sections are intended to ensure that the bearing migrates in a predetermined direction when a force acts on the bearing in an approximately radial direction. The production of these surface areas, which are offset from one another in the circumferential direction, means a high level of manufacturing complexity.

Out DE 102 53 262 A1 a rubber-metal bearing for a wheel suspension is known, comprising a rigid outer part 14, a rigid inner part 12 and a soft rubber element 13, which is arranged between the outer part 14 and the inner part 12, the inner part 12 being designed as a pin to which the rubber element 13 is fastened, preferably vulcanized on, and which has a conical fastening section 17 protruding from the rubber element 13 for connection to an adjacent component 19 .

As is well known, rubber is processed by vulcanization, which means a lot of energy and time.

The object of the invention consists in the development of an elastomer-metal bearing and a method for its production, which enables simple and inexpensive production and reduces the material costs.

This object is solved by the features of the first and twelfth claims. Advantageous configurations result from the dependent claims.

The elastomer-metal bearing according to the invention has at least one inner sleeve and an element made of elastic material on its outer diameter, the elastic element consisting of TPE (thermoplastic elastomer) and thereby forming a TPE-metal bearing for the first time.

The TPE material is used for the first time as an elastic element in an elastomer-metal bearing and offers significantly more favorable conditions in terms of production options than the use of rubber in a rubber-metal bearing.

In particular, it must be ensured that the TPE material used has elastic properties that are preferably similar or identical to the elastic properties of the rubber of a rubber-metal bearing.

The surface of the outer diameter of the inner sleeve can be smooth and/or at least partially roughened and/or at least partially profiled, so that a form-fitting connection is also provided, which ensures axial and/or radial position security.

The elastic element can be applied to the outer diameter of the inner sleeve, for example by means of injection molding. Alternatively, it is possible that the element is presented as a separate component and is pressed onto the outer diameter of the inner sleeve or is fastened by means of an adhesion promoter or adhesive.

In some cases, the elastomer-metal bearing has an outer sleeve and the elastic element made of TPE is arranged between the inner sleeve and the outer sleeve.

The outer sleeve can have an inner contour that is smooth and/or at least partially roughened and/or at least partially profiled, which ensures that the elastic element is secured in position.

The elastic element can also be applied to the inner contour of the outer sleeve by means of injection molding and the unit made up of the outer sleeve and elastic element can be mounted over the outer diameter of the inner sleeve, e.g. pressed or glued.

Alternatively, the elastic element can be applied to the outer contour of the inner sleeve by means of injection molding and the unit consisting of inner sleeve and element can be mounted, e.g. pressed or glued, into the inner diameter of the outer sleeve or the inner diameter of a component, in particular a chassis component.

In a further variant, the elastic area made of TPE can also be injected between the inner sleeve and the outer sleeve by injection molding.

The outer sleeve or a bearing recess can also be formed in a handlebar body.

The elastic element made of TPE preferably extends over the entire length of the inner sleeve.

The elastic element has a central area with a length and a wall thickness that increases axially on both sides in a bead-like area to a greater wall thickness and then reduces to a smaller wall thickness in an end area up to each front end of the inner sleeve.

Starting from the central area, the bead-like area first increases in its wall thickness at an incline, then falls at an incline and merges into the end area in a radius.

According to a further embodiment of the invention, the elastic element can consist of several layers.

There is the possibility that the elastic layers have different hardnesses, it also being possible for two or more layers to have the same hardness and one or more layers to have different hardnesses.

This makes it possible to build up or set the elasticity or a spring characteristic of the elastic element in a manner similar to that of a spring.

The use of TPE (thermoplastic elastomer) results in processing advantages compared to rubber. A more stable process with consistent quality, shorter process times and significantly less material waste are realized.

Direct processing in contact with a plastic housing (joint housing) is also possible.

The invention is explained in more detail below using exemplary embodiments.

• 1 die Draufsicht und
• 2 den Längsschnitt A-A gemäß 1 eines erfindungsgemäßen Elastomer-Metall-Lagers mit Innenhülse und auf dieser befindlichen elastischen Material aus TPE,
• 3 die Draufsicht und
• 4 den Längsschnitt B-B gemäß 3 eines erfindungsgemäßen Elastomer-Metall-Lagers, mit Innenhülse, Außenhülse und zwischen diesen befindlichen elastischen Material aus TPE,
• 5 die Draufsicht und
• 6 den Längsschnitt C-C gemäß 5 eines erfindungsgemäßen Elastomer-Metall-Lagers, mit Innenhülse, Außenhülse, gebildet durch einen Lenkerkörper und zwischen diesen befindliches elastisches Material aus TPE,
• 7 den Querschnitt und
• 8 den Längsschnitt D-D gemäß 7 eines TPE-Metall-Lagers, bei welchem das elastische Element 3 aus vier Schichten 3a bis 3d besteht.

Show it:

• 1 the top view and
• 2 according to the longitudinal section AA 1 an elastomer-metal bearing according to the invention with an inner sleeve and an elastic material made of TPE on it,
• 3 the top view and
• 4 according to the longitudinal section BB 3 an elastomer-metal bearing according to the invention, with inner sleeve, outer sleeve and elastic material made of TPE between them,
• 5 the top view and
• 6 the longitudinal section CC according to 5 an elastomer-metal bearing according to the invention, with inner sleeve, outer sleeve, formed by a handlebar body and elastic material made of TPE between them,
• 7 the cross section and
• 8th according to the longitudinal section DD 7 a TPE metal bearing, in which the elastic element 3 consists of four layers 3a to 3d.

In the 1 and 2 a variant of an elastomer-metal bearing 1 according to the invention is shown without an outer sleeve, which can be pressed into a corresponding bearing opening of a component that is not shown.

It has a longitudinal axis A and an inner sleeve 2, preferably made of metallic material (e.g. steel or aluminum) with an inner diameter 2.1 and an element 3 made of elastic material made of TPE (thermoplastic elastomer) on its outer diameter 2.2, which is preferably applied by injection molding .

The surface of the outer diameter 2.2 can be smooth or roughened or profiled, e.g. by knurling.

As an alternative to applying the elastic material by means of injection molding, the element made of elastic material (TPE) can also be designed as a separate component and pressed onto the outer diameter or otherwise attached, e.g. by means of an adhesion promoter or adhesive.

The element 3 is the same in all embodiments and is in the 2 described in more detail. It extends over the entire length L of the inner sleeve 2. Over a central area 3.1 with a length L1, the element 3 has a wall thickness b1, which increases to a wall thickness b2 on both sides in a bead-like area 3.2 and then to each front end of the inner sleeve 2 is reduced to a wall thickness b3 in an end region 3.3, which extends over a length L3. Starting from the area 3.1, the area 3.2 first increases in its wall thickness in a slope 3.2a and then falls in a slope 3.2b and merges in a radius R into the end area 3.3.

Due to the two bead-like areas 3.2 and the areas 3.3 reduced to a wall thickness b3 at the end, a pivoting movement between the inner sleeve and the outer component in the form of an outer sleeve or another component, in the bearing bore of which the inner sleeve with the elastic area 3 is seated, is possible and it an axial securing is realized by the bead-like areas. The pivoting movement is made possible by the end region 3.3, which has a reduced wall thickness.

In the 3 and 4 an elastomer-metal bearing according to the invention is shown, with inner sleeve 2, outer sleeve 4 and element 3 made of elastic material made of TPE located between them.

The length L4 of the outer sleeve 4 extends approximately to the highest areas of the two bead-like areas 3.2 of the elastic element 3 on the circumferential side

The inner contour 4i of the outer sleeve has a central area with an inner diameter 4d1 and widens on both sides of its inner contour 4i outwards to an inner diameter 4d2, which essentially corresponds to the outer diameter (not designated) of the elastic element 3 in the area of the greatest wall thickness of the bead-like area 3.2.

In the initial state shown, the longitudinal axis A is aligned with the longitudinal axis A4 of the outer sleeve 4, which is shown here by a dash-dot line. If the outer sleeve 4 is deflected relative to the inner sleeve 2, indicated by the narrowly dashed longitudinal axis A4, the elastic element causes a pivoting movement in a swivel angle between the inner and outer sleeve is possible.

The connection between the elastic area/element 3 and the outer diameter 2.2 of the inner sleeve and/or the inner contour 4i of the outer sleeve 4 can be made on their smooth surfaces without tools or with tools in the form of adhesion promoters and/or adhesives. Furthermore, the outer diameter 2.2 of the inner sleeve and/or the inner contour 4i of the outer sleeve 4 can be roughened or profiled, e.g. by knurling.

In a preferred variant, the inner sleeve 2 and the outer sleeve 3 are positioned in an injection mold and the element/elastic area made of TPE is injected between them by injection molding.

Alternatively, the elastic area made of TPE can only be injected on the inside of the outer sleeve 4 and then the unit made up of the outer sleeve 4 and the element 3 can be pressed over the inner sleeve 2 .

It is also possible to inject the element 3 onto the outer diameter 2.2 of the inner sleeve 2 and to mount this unit in the outer sleeve 4.

The unit consisting of inner sleeve 2, elastic element 3 and outer sleeve 4 can be used as an elastomer-metal bearing in a recess of a component, e.g. a chassis component, preferably pressed.

The inner sleeve is preferably made of steel or aluminum and the outer sleeve is also made of a metallic material (e.g. steel or aluminum).

However, there is also the possibility of manufacturing the inner sleeve 2 and/or the outer sleeve 4 from plastic that is harder than the material of the elastic element 3.

In this case, a plastic made of fiber-reinforced polyamide is preferably used for the inner and/or outer sleeve.

For example, if the inner sleeve 2 is made of metal, it is also possible to produce the elastic element 3 and the outer sleeve 4 from plastic by injection molding.

If necessary, a 2-component injection molding process (2K injection molding) can also be used for this, in which, for example, first the hard component in the form of the inner sleeve 2 or the outer sleeve 4 and then the soft component in the form of the elastic element 3 is produced.

The outer sleeve 4 made of plastic (not shown) advantageously has a peripherally closed sleeve-like area on the inside, from which rib-like projections extend radially outwards.

The ends of the projections pointing radially outwards are connected to one another with an outer plastic ring and are designed in one piece with it.

In 5 is the top view and in 6 the longitudinal section CC according to 5 an elastomer-metal bearing according to the invention, with inner sleeve 2, outer sleeve 4, formed by a link body 5 for a chassis of a vehicle and an element 3 located between these and made of elastic material made of TPE.

The structure is essentially identical to the variant in the 3 and 4 is shown, except that the outer sleeve is formed by the handlebar body 5.

For example, the unit consisting of the inner sleeve 2 and the elastic element 3 was pressed into the bearing recess of the handlebar body 5 .

The pressing of the unit of inner sleeve 2 and elastic element 3 into a bearing recess of a component or into the inner diameter of the outer sleeve is preferably carried out with an oversize to the bearing recess, so that the elastic element is subjected to a pretension. The pre-tension ensures that the position between the components is secured.

Alternatively, the link body or another vehicle component with a bearing recess and the inner sleeve can also be positioned relative to one another in an injection mold and the elastic element made of TPE can be injected into the area/space formed between the components.

Shaped elements (e.g. roughening, knurling or other elevations/depressions) on the outer diameter of the inner sleeve and/or the inside diameter of the bearing recess of the outer sleeve or the vehicle component achieve an axial and/or radial position fixation, since the elastic element engages in these shaped elements and thus also a positive connection is created.

Alternatively, it is also possible to use an elastomer-metal bearing 3 and 4 with the Press the outer diameter of the outer sleeve into a corresponding bearing recess of a component. The component can be, for example, a chassis component, for example a chassis link, a link rod or a coupling rod.

The two bead-like areas 3.2 also produce an undercut in the TPE area 3, in which the inner contour 4i of the outer sleeve 4 engages, thereby reducing the risk of the outer sleeve 4 shifting axially relative to the inner sleeve 2.

According to the method, an elastomer-metal bearing in the form of the TPE-metal bearing according to the invention is produced in a first possible variant in that a TPE material is first applied to an inner contour 4i of an outer sleeve 4 by means of injection molding and thereby an elastic element 3 inside of the outer sleeve 4 is generated, which adjoins the inner contour or the inner diameter of the outer sleeve. The unit consisting of the outer sleeve 4 and the elastic element 3 is then fitted over an outer contour 2.2 of an inner sleeve 2, preferably pressed in with excess or alternatively fastened by a material connection, e.g. by means of an adhesive or primer

In a second production variant, the TPE material is first applied to the outer contour 2.2 of the inner sleeve 2 by means of injection molding, whereby the elastic element 3 is produced on the outer diameter or the outer contour of the inner sleeve 2. Then the unit consisting of the inner sleeve 2 and the elastic element 3 is mounted in the inner contour 4i or the inner diameter of the outer sleeve 4 or an inner diameter of a component, preferably oversized or alternatively fastened by material bonding, e.g. using an adhesive or primer

According to a third variant, the inner sleeve and outer sleeve are positioned relative to one another such that the inner sleeve is inside the outer sleeve, with the inner diameter or inner contour of the outer sleeve and the outer contour or outer diameter of the inner sleeve being spaced apart by a gap.

The TPE material is injected into this gap by injection molding and forms the elastic element of the TPE bearing.

Before the TPE material is injection molded, the surface of the outer contour (2.2) of the inner sleeve (2) and/or the inner contour (4i) of the outer sleeve (4) or the inner diameter of the component can be roughened at least in areas and/or profiled at least in areas in order to to achieve better adhesion and security against twisting and axial fixation of the TPE material or the elastic element.

The roughening or the profiling can be produced, for example, by machining and/or forming, erosive machining methods or other known methods.

In the 7 and 8th a further variant of the solution according to the invention is shown.

Here the elastic element consists of four layers 3a to 3d.

The inner first layer 3a arranged on the inner sleeve 2, a second layer 3b adjoining it radially. Around this there is a third layer 3c and on the outside of the outer sleeve 4 a fourth layer 4d.

For example, the first layer 4a and the fourth layer 4d are the hardest layers and the layer 3b has a lower hardness than 4a and 4d and the layer 4c in turn has a lower hardness than the third layer 3c.

Alternatively, only two or three layers or more than four layers can also be used.

In the 7 and 8th the outer sleeve 4 has several openings 4.1 distributed over its circumference, which are filled with the material of the outer layer (here 3d) of the elastic element by injection molding. Eight breakthroughs 4.1 are shown here as an example, which are designed like longitudinal slots.

However, the breakthroughs can also be in the form of bores and other breakthroughs.

According to an exemplary embodiment that is not shown, openings or recesses can also be provided in the inner sleeve, into which the elastic material flows during injection molding.

There is also the possibility, when using only one elastic element, which consists of only one layer/component, that there are openings and/or recesses in the outer sleeve and/or the inner sleeve, into which one material of the elastic element flows during injection molding .

The TPE used is selected depending on the load and temperature influences s, environmental influences, chemicals such as oil, type of fuel, etc.

The suitable TPE for the respective application can be determined by reference tests.

Appropriate overviews of the properties of the TPE materials are available to those skilled in the art.

For applications that require a rather low hardness of the elastic component / the elastic element, TPS - materials (styrene block copolymers) are suitable, whereas, for example, TPC (thermoplastic copolyester) is characterized by high operating temperatures. The selection of the suitable TPE's depends on the application to be reconsidered or determined for the application and, if necessary, to carry out reference tests.

Particularly for the chassis area, the outer sleeve can also be made of plastic, for example PA6.6 or PA6, particularly if a temperature range of -40°C to 100°C is to be expected.

Compatibility with fats, oils, glycol, fuels, salts, etc. is also important for the chassis area.

The described advantages of the bearing according to the invention are independent of the TPE type.

Surprisingly, it was found in numerous tests that with the chassis mounts in the form of the elastomer-metal mounts according to the invention with TPE as the elastic component, the required dynamic transmission properties, as well as the psychoacoustic and driving-dynamic properties can also be met via the previously achievable properties of conventional rubber-metal mounts.

The use of TPE as an elastic component in an elastomer-metal bearing between the inner and outer sleeve or inner sleeve and bearing recess of a component has not been known to date.

QUOTES INCLUDED IN DESCRIPTION

This list of documents cited by the applicant was 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.

Patent Literature Cited

• DE 102010037891 A1 [0005]
• DE 3240981 A1 [0006]
• DE 10253262 A1 [0007]

Claims (13)

Elastomer-metal bearing (1) with an inner sleeve (2) and an element (3) made of elastic material located on its outer diameter (2.2), characterized in that the elastic element (3) consists of TPE (thermoplastic elastomer), whereby a TPE metal bearing is formed. Elastomer-metal bearing (1), characterized in that the surface of the outer diameter (2.2) is smooth and/or roughened at least in areas and/or profiled at least in areas. Elastomer-metal bearing (1) according to one of the preceding claims, characterized in that the elastic element is applied to the outer diameter (2.2) of the inner sleeve (2) by means of injection molding or that the element (3) is listed as a separate component and on the Outer diameter (2.2) of the inner sleeve (2) is pressed or by means of an adhesion promoter or adhesive. is attached. Elastomer-metal bearing (1) according to one of the preceding claims, characterized in that it has an outer sleeve (4) and that the elastic element (3) made of TPE is arranged between the inner sleeve (2) and the outer sleeve (4). Elastomer-metal bearing (1) according to one of the preceding claims, characterized in that the outer sleeve (4) has an inner contour (4i) which is smooth, at least partially roughened or at least partially profiled. Elastomer-metal bearing (1) according to one of the preceding claims, characterized in that the elastic element (3) is applied to the inner contour (4i) of the outer sleeve (4) by means of injection molding and the unit consisting of the outer sleeve (4) and element ( 3) is mounted (pressed or glued) over the outer diameter (2.2) of the inner sleeve (2). Elastomer-metal bearing (1) according to one of the preceding claims, characterized in that the elastic element (3) is applied to the outer contour (2.2) of the inner sleeve (2) by means of injection molding and the unit consisting of the inner sleeve (2) and element ( 3) is mounted (pressed or glued) in the inner diameter (4i) of the outer sleeve (4) or the inner diameter of a component, in particular a chassis component. Elastomer-metal bearing (1) according to one of the preceding claims, characterized in that the elastic area (3) made of TPE is injected between the inner sleeve (2) and the outer sleeve (4) by injection molding. Elastomer-metal mount (1) according to one of the preceding claims, characterized in that the outer sleeve (4) is formed in a link body (5). Elastomer-metal bearing (1) according to one of the preceding claims, characterized in that the elastic element (3) made of TPE extends over the entire length (L) of the inner sleeve (2). Elastomer-metal bearing (1) according to one of the preceding claims, characterized in that the elastic element consists of several layers. Method for producing an elastomer-metal bearing according to one of the preceding claims, characterized in that a TPE material - is first applied to an inner contour (4i) of an outer sleeve (4) by means of injection molding and thereby an elastic element (3) within the Outer sleeve (4) is produced and then the unit made up of outer sleeve (4) and elastic element (3) is assembled via an outer contour (2.2) of an inner sleeve (2) or - first by injection molding onto the outer contour (2.2) of the inner sleeve (2) an elastic element (3) is thereby produced on the outer sleeve (4) and the unit consisting of the inner sleeve (2) and elastic element (3) is then mounted in the inner contour (4i) of the outer sleeve (4) or an inner diameter of a component or - between the outer contour (2.2) of the inner sleeve (2) and the inner contour (4i) of the outer sleeve (4) or an inner diameter of a component is injected by injection molding and a T PE metal bearing is generated. procedure after claim 12 , characterized in that before the TPE material is injection molded, the surface of the outer contour (2.2) of the inner sleeve (2) and/or the inner contour (4i) of the outer sleeve (4) or the inner diameter of the component is roughened at least in areas and/or at least in areas is profiled.

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