WO2012116902A1

WO2012116902A1 - Component, in particular for a rolling bearing or plain bearing

Info

Publication number: WO2012116902A1
Application number: PCT/EP2012/052823
Authority: WO
Inventors: Wolfgang Braun; Sergej Schwarz; Kerem KÖKSAL; Tim Matthias Hosenfeldt; Gudrun Martin; Jürgen WINDRICH; Daniel PÖPPERL; Helmut Schillinger; Rainer Pflug
Original assignee: Schaeffler Technologies AG & Co. KG
Priority date: 2011-02-28
Filing date: 2012-02-20
Publication date: 2012-09-07
Also published as: DE102011004803A1

Abstract

Component, in particular for a rolling bearing or plain bearing, comprising a metallic main body having at least one cylindrical face, wherein a thermoplastic shrink tube is shrunk onto the cylindrical face.

Description

Name of the invention

Component, in particular for a rolling or sliding bearing Description

Field of the invention

The invention relates to a component, in particular for a rolling or sliding bearing, comprising a metallic base body having at least one cylindrical surface.

Background of the Invention A component having a cylindrical surface that frictionally contacts another surface is subject to wear. Wear occurs, for example, when a cylindrical pin is guided in a bore and / or rotated or when several components with cylindrical surfaces perform a sliding or rolling movement. Under extreme conditions of use such as elevated temperature and / or lack of lubrication special demands are placed on the components of the frictional contact. For example, one of the two friction partners can be provided with a wear-resistant surface so as not to damage the other friction partner. However, it is desirable that the wear occurs only with a delay, in order to avoid premature failure of the component. In this context, it is known to press a brass sleeve onto a metallic base body with a cylindrical surface. The soft brass forms a weary friction partner. Such brass sleeves or treads of brass z. B. used in plain bearings.

Alternatively, the metallic base body with a cylindrical surface may have a coating. For this purpose, a variety of different wear-resistant coating materials is known. For the Bonding coatings and coatings made of PEEK (polyether ether ketone), which are temperature stable up to approx. 250 ° C, have proven particularly suitable for use at high temperatures. A provided with a lubricating bearing is known from DE 101 18 365 A1. In the publication DE 20 2008 006 915 IM a bearing with a sliding material is described, which may consist inter alia of PEEK.

However, both the brass sleeves mentioned and the coatings also have disadvantages. Brass bushes are relatively massive and increase the overall mass considerably. In order to press the brass bushing, the component must meet increased requirements for the tolerances. Coatings with a bonded coating are comparatively thin, a layer thickness of about 25 μm is generally not exceeded. In places with increased wear and high surface pressures, the layer is therefore quickly worn out.

A similar problem arises in components for rolling or sliding bearings, in which an electrical insulation is required. For this purpose, it is known to provide the cylindrical surface of a bearing component with a ceramic coating in order to achieve a current isolation. Alternatively, certain bearing components, for example housings, can be provided with a synthetic resin coating. The problem is, however, that such synthetic resin coatings are generally not rollable, accordingly, synthetic resin coatings are not suitable for running surfaces of a rolling or sliding bearing.

Summary of the invention

The invention is therefore based on the object to provide a component for a rolling or sliding bearing, which has good wear properties and ensures electrical insulation. To solve this problem, it is provided according to the invention in a component of the type mentioned that a thermoplastic shrink tube is shrunk onto the cylindrical surface. The invention is based on the finding that a shrink tube can form a sliding layer in a cylindrical sliding pair, which is characterized by good wear properties and high temperature resistance. In addition, the shrink tube ensures electrical insulation. The component according to the invention thus comprises the metallic base body with at least one cylindrical surface, onto which a thermoplastic heat-shrinkable tube is firmly shrunk by means of heat treatment, which at least partially covers the cylindrical surface.

In the case of the rolling element or sliding bearing component according to the invention, the shrinking tube may comprise one of the following materials or a mixture thereof: polyetheretherketone (PEEK), polytetrafluoroethylene (PTFE), polymethyl methacrylate (PMMA), polyvinyl chloride (PVC), polyvinylidene fluoride (PVDF), polyolefin. With all the materials mentioned, a sliding layer with good wear properties, high temperature resistance and the required electrical insulation can be obtained. However, particularly preferred is a PEEK existing shrink tube. The invention is particularly well suited for components of a rolling or sliding bearing, which are designed as a bearing outer ring, bearing inner ring, bearing cage, sleeve, bush or cylindrical rolling elements. In each case, at least one cylindrical surface is present, to which the thermoplastic shrink tube is shrunk. The application of the shrink tube is comparatively fast compared to other coating methods that require complex or multi-step process steps. In order to influence the hardness of the metallic base body, it can be provided in the component according to the invention that the metallic base body is hardened and / or case-hardened and / or carbonitrided and tempered. Accordingly, various curing methods are available to provide a metallic body having a desired hardness. The hardening takes place before the cylindrical shrink tube is shrunk.

In order to achieve particularly good adhesion of the shrink tubing to the metallic base body, the metallic base body can have an adhesion-promoting layer, in particular a phosphate layer and / or a silane layer and / or a passivating layer produced by a hexafluoro derivative. In the case of the component according to the invention, it is preferred that the shrunk-on shrink tubing has a thickness of 50 μm to 500 μm, in particular the thickness can be approximately 100 μm.

In addition, the invention relates to a bearing assembly having at least two relatively movable to each other movable, forming a friction pair components, of which at least one component has a metallic base body with at least one cylindrical surface.

The bearing assembly according to the invention is characterized in that on the cylindrical surface of a thermoplastic shrink tube is shrunk.

In addition, the invention relates to a method for producing a component with a metallic base body having at least one cylindrical surface, in particular for a rolling or sliding bearing. The inventive method is characterized in that on the cylindrical surface, a thermoplastic shrink tube is shrunk.

In the method according to the invention it can be provided that the shrink tube is shrunk by means of hot air or induction heat.

Further embodiments of the invention are described in the subclaims

Short description of the drawing

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

Detailed description of the drawing

1 shows a metallic base body and a shrink tube before shrinking;

Fig. 2 shows an inventive component after shrinking the

Shrinkable sleeve; FIG. 3 shows a perspective view of the component according to the invention shown in FIG. 2; FIG. and

Fig. 4 shows another embodiment of a component according to the invention.

Fig. 1 shows a sectional view of a metallic base body 1, which is formed as a shaft and has a cylindrical surface 2. The main body 1 is surrounded by a shrink tube 3, the thickness of For the sake of illustration in Fig. 1 is shown on an enlarged scale. In fact, the thickness of the shrink tube is 3 z. B. 100 μιτη, it is thus a film that is extremely thin compared to the base body 1. Fig. 1 shows the shrink tube 3 in the initial state, that is, in the non-shrunken state. The shrink tube 3 is made of a thermoplastic, in the illustrated embodiment, this is PEEK (polyetheretherketone).

FIG. 2 shows the component 4 consisting of the main body 1 and the shrinking tube 3 after the shrinking tube 3 has been shrunk. When the heat is supplied by hot air or by inductively generated heat, the shrinking tube 3 shrinks until it lies completely against the base body 1 and surrounds it , On the outside of the component 4, a continuous layer is thus formed, which has good wear properties and additionally lends an electrical insulation.

As can be seen in the perspective view of FIG. 3, the shrink tube 3 extends only over part of the length of the main body 1. However, other embodiments are of course possible, in which the heat-shrinkable tube completely envelops the cylindrical surface.

In the case of the component 4 shown in FIGS. 1 to 3, the heat-shrinkable tube 3 forms a sliding layer with good wear properties with a high temperature resistance. The wall thickness of the shrink tube 3 can be selected depending on the intended use between 50 pm and 500 μηι, a thickness of about 100 μηπ is preferred. Technically, the attachment of the shrink tube 3 is comparatively simple, by using a shrink tube whose inner diameter is greater than the initial diameter of the body. Accordingly, the shrink tube can be easily applied to the body and then shrunk by supplying heat, so that a firm connection is formed. Compared to a bonded coating is the through The heat shrink layer formed layer thicker and thus much more wear resistant.

The component 4, together with at least one further component, forms a bearing arrangement, wherein the components which are movable relative to one another form a friction pairing.

The component 4 shown in Figures 1 to 3 can be used for example in rolling rods for woodworking machines. These rolling rods are guided and stored by means of a cylindrical bolt.

4 shows a component 5 for a bearing arrangement in a sectional view, comprising a main body 6 with a cylindrical surface 7, the main body 6 is provided on its outer side with a heat-shrinkable tube 8. The shrink tube 8 forms a layer with good tribological properties, which simultaneously ensures electrical insulation.

The base body 6 can be made of a cost-effective steel material such as 16MnCr5, C45, 100Cr6, 31 CrMoV9 or 80Cr2. In the exemplary embodiment shown in FIG. 4, the metallic main body 6 consists of the material 100Cr6, which is case hardened before the application of the shrink tube 8. In other embodiments, the metallic base body may also be carbonitrided and tempered. On the metallic base body 6, a phosphate layer (ZnPh, FePh) is applied as an adhesion-promoting layer. Alternatively, a silane layer may be used as the primer layer. As a further alternative, a passivation by means of a Haxafluo- ro derivative (Zr, Ti, Si or mixtures thereof) may be applied.

The heat-shrinkable tube 8, which serves as cover layer and functional layer, can be applied directly or with the mentioned substructure to the base body 6. To minimize the tendency to adhesion to the metallic base body 6, a high abrasion resistance, a high chemical resistance, even in contact with oil, high mechanical strength and a high hardness-to-E-module ratio to achieve while electrical insulation, the shrink tube may contain no metallic components. Accordingly, the shrink tubing may be made of PEEK, PTFE, PMMA, PVC, PVDF, an olefin, or a mixture thereof.

Since the component 5 shown in FIG. 4 has a wear protection through the heat-shrinkable tube 8, the counter-body or the friction partner is also protected on account of the outstanding tribological layer properties. By using a heat-shrinkable tubing as a coating, it is possible to use a cost-effective material as base material (16MnCr5, C45, 100Cr6, 3CrMoV9, 80Cr2) for the metallic base body. Costly ceramic rolling elements can be replaced by the coating. The coated components for a bearing assembly such as a sliding or roller bearing have better mechanical properties, since the layer formed by the shrink tubing takes over the tribological and current insulating properties and the tough round steel body carries the mechanical loads. The illustrated and described embodiments can be modified by varying the layer thickness and the number of separation layers. For example, only rolling elements may be coated or an inner ring or an outer ring may additionally be coated.

The shown in the embodiments component for a bearing assembly such as a rolling or sliding bearing can also for other functional units such as support and plug-in elements, rolling bearing components, release bearing (sleeve), piston pin, plain bearing pins, bushings, control piston, linear guides, universal joints and for other mechatronic systems and parts are used. The component 5 shown in FIG. 4 is a universal joint bush, which on the one hand has to be electrically insulated and, on the other hand, has to run with low noise. Both can be achieved with the coating by the shrink tube 8. For the production of the component 5 shown in Fig. 4 of the metallic base body 6 is cleaned with alcohol, alternatively, this can be done with C0 ₂ . Subsequently, a primer is applied in the form of a phosphating or by a silane layer. The heat shrink tubing used is coated on the inside with a hot melt adhesive. The shrink tube 8 is cut to size and brought to the desired position of the base body 6, at which a sliding and insulating surface is to arise. The main body 6 is heated by induction, by a heating furnace or a burner to the temperature at which the shrinkage of the shrink tube 8 enters. Subsequently, the finished component 5 is cooled to about 40 ° C, so that further assembly work can be carried out. Manufacturing-technical savings can be achieved if the shrinkage or melting temperature of the shrink tube is selected so that it corresponds to the tempering temperature of the hardened metallic base body 6. In this case, the renewed heating of the main body 6 is omitted, instead, the shrinking can be done directly after starting.

LIST OF REFERENCE NUMBERS

1 main body

2 cylindrical surface

3 shrink tubing

4 component

5 component

6 basic body

7 cylindrical surface

8 shrink tubing

Claims

claims

Component, in particular for a rolling or sliding bearing, comprising a metallic base body having at least one cylindrical surface, characterized in that on the cylindrical surface (2, 7), a thermoplastic shrink tubing (3, 8) is shrunk.

Component according to claim 1, characterized in that the heat-shrinkable tube (3, 8) comprises one of the following materials or a mixture thereof: polyetheretherketone (PEEK), polytetrafluoroethylene (PTFE), polymethyl methacrylate (PMMA), polyvinyl chloride (PVC), po lyvinylidene fluoride (PVDF), polyolefin.

Component according to claim 1 or 2, characterized in that it is designed as a bearing outer ring, bearing inner ring, bearing cage, sleeve, bush or cylindrical rolling elements.

Component according to one of the preceding claims, characterized in that the metallic base body (1, 6) has an adhesion-promoting layer, in particular a phosphate layer and / or a silane layer and / or a passivation layer produced by a hexafluoro derivative.

Component according to one of the preceding claims, characterized in that the shrink tubing (3, 8) has a thickness of 50 μιη to 500 μιτι, in particular a thickness of approximately 100 μιη

Bearing arrangement with at least two relatively movable, a friction pair forming components, of which at least one component has a metallic base body with at least one cylindrical surface, characterized in that on the cylindrical surface (2, 7) a thermoplastic shrink tube (8) is shrunk. A method for producing a component with a metallic base body having at least one cylindrical surface, in particular for a rolling or sliding bearing, characterized in that on the cylindrical surface, a thermoplastic shrink tube is shrunk.

A method according to claim 7, characterized in that the shrink tube is shrunk by means of hot air or induction heat.

A method according to claim 7 or 8, characterized in that on the metallic base body prior to application of the shrink tube, an adhesion promoting layer is applied, in particular a Phosphatschicht and / or a silane layer and / or a Passivierungsschicht generated by a hexafluoro derivative.

Method according to one of claims 7 to 9, characterized in that one of the following materials or a mixture thereof is used as a shrink tube: polyetheretherketone (PEEK), polytetrafluoroethylene (PTFE), polymethyl methacrylate (PMMA), polyvinyl chloride (PVC), polyvinylidene fluoride ( PVDF), polyolefin.