DE102008027596A1 - Method for producing a bearing component - Google Patents

Abstract

The present invention relates to a method for producing a bearing component, for example a connecting rod, wherein a Pleuelrohling is produced by a forming process or a molding process and in a connecting rod of the Pleuelrohlings a bearing ring is inserted, wherein the Pleuelrohling when inserting the bearing ring has a temperature of more than 300 ° C. When inserting the bearing ring, the heat of the forming or Urformvorgangs can be used.

Description

The The invention relates to a method for producing a bearing component according to claim 1.

Bearing components, such as B. connecting rods, which are used in modern engines, are especially at their bearing eyes very high mechanical loads exposed. To the bearing eyes tribologically on the stored therein Materials, it is common to use special bearing materials to insert into the bearing eyes. These are often made of softer ones Material as the stored materials, thus a material abrasion is minimized.

In Internal combustion engines are widely used as cracked steel connecting rods. Crackpleueluel be first made in one piece, then with broken notches or provided with a laser notch and then deliberately broken into two parts (Cracking). The fracture surfaces are in terms of strength, Cost and manufacturing accuracy optimized. Both parts fit the connecting rod assembly exactly screwed together. Connecting rod and connecting rod cover must due to the individual fracture geometry always stay together.

In the EP 0635 104 B1 a connecting rod is described, which is equipped with a bearing layer, wherein the bearing layer is shared with the connecting rod by fracture separation.

In the DE 10 2004 041 042 A1 It is described how a bearing ring is fitted in the form of a press fit in a bearing eye.

In the DE 103 44 723 B4 a bearing component is described which has a galvanically applied sliding layer.

task The invention is to provide a bearing component, the opposite the state of the art is cheaper to produce and It has good mechanical properties.

The Solution to the problem consists in a bearing component with the Features of claim 1.

The Method for producing a bearing component, for example a Pleuels is that a component blank of the bearing component produced by a thermoforming or a forming process becomes. It is envisaged that a component blank by a thermal Forming or thermal molding process is produced and then inserted into a bearing eye of the component blank, a bearing ring is, wherein the component blank when inserting the bearing ring has a temperature that allows sintering of the bearing ring. At the Insertion of the bearing ring takes place by sintering operations the metal of the connecting rod and the corresponding surface of the bearing ring instead of a sintering, which the adhesion essential supported. that the bearing ring immediately after the thermal Umform or Urformverfahren before cooling the component is inserted into the bearing eye of the component blank.

It is particularly useful, the process heat of the original or forming process for the component blank use, that is the bearing ring immediately after this thermal process step and insert the process heat for to use the sintering process. Of course it is also possible the component initially controlled or uncontrolled to cool to an intermediate temperature or room temperature and then to a defined sintering temperature for insertion to heat the bearing ring again.

Essential is that a bearing ring, which is a later storage area represents, in a bearing eye of the component blank at a temperature is inserted, which sintering processes between bearing ring and component permits. The bearing ring is designed so that he can press on the component. For greasing of the bearing ring, the component blank, depending on the nature of the contact surface forming surface of the bearing ring, a temperature of more than 300 ° C, preferably more than 400 ° C, in particular more than 1150 ° C on. by virtue of The high temperatures of the component blank can be diffusion processes and sintering processes between the closely contacting metal surfaces take place and there is a solid positive and material connection.

Under the forming process for the production of the component in which a semifinished product under an external force and under Supply of heat, usually in a designated Form to a blank or already formed into a finished component becomes. The most important forming process here is forging. Under archetypes is understood as a manufacturing process, wherein a malleable, often liquid or thixotropic mass under application of an external force (including gravity), usually at elevated temperature is brought into a mold, whereupon a solidification of the mass takes place and a component blank or a finished component shown becomes. Examples of prototypes are metal casting processes (Die casting, sand casting, thixo casting) or injection molding.

A significant advantage of the method according to the invention is that the process heat from the component production, in particular the forging heat of a forged steel component, is used for sintering the bearing ring. The bearing ring is therefore preferred directly to the Component manufacturing introduced into the hot component. In general, the process heat is sufficient for sintering, so that no additional heating or temperature after-treatment is required.

So can the forming heat energy use what leads to energy savings in the manufacturing process.

In Another embodiment, the temperature for short Time to support the sintering process kept constant be prevented or the rapid cooling. For this purpose, a holding time of 5 to 10 minutes at or is preferred near the temperature of inserting the bearing ring selected.

The Urformverfahren is preferably a forging process, wherein the component blank preferably consists of a forged steel.

It is appropriate, the bearing ring in the bearing eye pressing, thereby increasing the strength of the connection between bearing eye and bearing ring is raised again. The bearing eye of the Component blanks are drawn from the sintering temperature during cooling to room temperature together. Preferably, the bearing ring is in colder Condition, introduced, so that the thermal shrinkage of the bearing eye larger is the one of the bearing ring. As a result, the component shrinks on the bearing ring, which supports the sintering processes and an additional interference fit is built up. By adapted geometry of bearing eye and bearing ring this can Tightening effect further amplified.

To the insertion of the bearing ring in the bearing eye, the bearing eye and the bearing ring located therein by a fracture separation method, also called crackers, separated and reassembled become. This allows a shaft to be stored in the bearing eye deploy. For the fracture separation it is expedient that the bearing ring, possibly also the bearing eye a predetermined breaking point having. In particular, the bearing ring already before insertion a breaking point on.

Of the Bearing ring is usually designed in one piece, but it can Also, a two- or multi-part bearing ring appropriate be. This facilitates the later fracture separation.

Of the Bearing ring consists of one for the stored therein Shaft tribologically particularly favorable material, preferably the bearing ring consists of a brass alloy or a Bronze alloy. This can also be on the usual Lagermetalllegierungen be resorted to.

The Brass, bronze and bearing metal alloys have the advantage that they are low melting and therefore in process heat the original or deformation of the component blank sinterable are.

Of the Bearing ring can also be on a contact surface with the component blank or the bearing eye a solder material, for example on the basis alloys of Zn, Ag, Sn or Cu. Through the solder material the connection to the bearing component can be improved. The Solder material can both melt at the given process temperature as well as only by sintering processes to the underground tie. The transitions are fluent.

Further advantageous embodiments and special features are on hand the following special description and the two figures explained in more detail.

there demonstrate:

1 , a blank of a connecting rod with pressed bearing ring and

2 a finished connecting rod with pressed-in bearing ring.

In 2 is a finished connecting rod 2 shown that z. B. serves as a connection between a piston in an internal combustion engine and a crankshaft. The manufacturing process of this connecting rod 2 will be described in more detail below.

In a forging tool, not shown, a forged steel semi-finished product, also not shown, is produced by a forging process to the Pleuelrohling 4 reshaped. The forging temperature is between 1000 ° C and 1200 ° C.

The connecting rod blank 4 has two bearing eyes, one under bearing eye 6 in which the crankshaft is mounted in a fully assembled engine and an upper bearing eye 16 , which will not be discussed in further detail (which, however, can be treated equally) and in which a pin is mounted which is in communication with the piston.

The connecting rod blank 4 is taken from the forging tool, with a bearing ring 8th , which may also be referred to as a socket, and in this example has room temperature, in the bearing eye 4 is pressed. The connecting rod blank 4 in this case has a temperature of about 350 to 450 ° C. This temperature is suitably adapted to the application temperature of the solder material or the sintering temperature of the bearing ring surface.

When pressing in, the bearing ring points 8th one equal to or slightly larger outer diameter than the inner diameter of the bearing eye 6 at the respective Einpresstemperatur.

The bearing ring 8th points on its outside, that of an inside 7 of the bearing eye 6 facing side on a tin-based solder on. The solder may also consist of a zinc or copper alloy, which may contain the other mentioned elements as alloying ingredient. The solder melts when pressed at least partially and connects so with the material of Pleuelrohlings 4 , In this alloying process, which in principle can also take place without the addition of solder material between the bearing ring material and the Pleuelrohlingmaterial, is from the first purely form-fitting a cohesive connection.

This connection is reinforced by the connecting rod blank 4 cools, resulting in a minor shrinkage process, in which also reduces the diameter of the bearing eye. By shrinking the bearing eye 6 this is additionally directed radially inward on the bearing ring 8th pressed.

After pressing in the bearing ring 8th into the bearing eye 4 Further processing of the connecting rod blank takes place 4 and the pressed-in bearing ring 8th , The storage 8th is thereby machined and pre-turned with a corresponding allowance to the final dimension.

After pre-twisting, the fracture separation takes place, the so-called cracking. In this known method, the Pleuelrohling 4 in the area of the bearing eye 6 at a specially attached predetermined breaking point, such as a notch broken. A breaking point 10 is also in the bearing ring in this example 8th contain. The relatively brittle forging material of Pleuelrohlings breaks without significant elastic deformation in two fragment halves 18 . 20 and leaves a unique fracture. Both fragments halves th 18 . 20 fit so closely together that no amount of mechanical processing could make such a good fit.

The resulting fragments 18 and 20 be through a screw connection 14 joined together. Subsequently, a fine machining by a honing process, finally, if necessary, a lubricating varnish on the sliding surface of the bearing ring 8th be applied.

In this example it is described that the bearing ring 8th is pressed into the Pleuelrohling when it is still heated by the forming process. Should the process chain require it, the connecting rod blank can also be reheated later and the bearing ring pressed in later, which of course results in additional energy expenditure.

Of the Bearing ring can also be introduced by a so-called rolling process be, with the bearing ring moves cyclically, rotated or back and forth is moved.

Further possible components for the application of the described Procedure are all kinds of bearings. In addition to the connecting rod could this technique also in a bearing block for a crankshaft be applied, the bearing chair usually made of an aluminum alloy is poured.

2

pleuel

4

Pleuelrohling

6

connecting rod

7

inside connecting rod

8th

bearing ring

10

Breaking point

12

connecting rod

14

screw

16

upper bearing eye

18

fragment

20

fragment

QUOTES INCLUDE IN THE DESCRIPTION

This list The documents listed by the applicant have been automated generated and is solely for better information recorded by the reader. The list is not part of the German Patent or utility model application. The DPMA takes over no liability for any errors or omissions.

Cited patent literature

• - EP 0635104 B1 [0004]
• DE 102004041042 A1 [0005]
• - DE 10344723 B4 [0006]

Claims (20)

Method for producing a bearing component with a bearing seat, in particular a connecting rod, wherein a component blank by a thermal forming process or thermal forming process is produced and then in a bearing eye of the component blank a bearing ring is used, wherein the component blank during insertion of the bearing ring has a temperature which is a sintering of the Bearing ring allows. Method according to claim 1, characterized in that that the bearing ring immediately after the thermal Umform or Urformverfahren before cooling the component in the bearing eye of the component blank is inserted. Method according to claim 1 or 2, characterized that the component blank has a temperature of more than 300 ° C. having. Method according to claim 1, 2 or 3, characterized that at least the surface of the bearing ring, in contact comes with the bearing eye of the component blank, from a at temperatures of 300 to 1100 ° C sinterable material. Method according to one of the preceding claims, characterized in that the component blank with inserted Bearing ring for at least 5 minutes at sintering temperature is held. Method according to one of the preceding claims, characterized in that the bearing ring of a brass alloy or a bronze alloy. Method according to one of the preceding claims, characterized in that the bearing ring on contact surfaces having a solder material with the component blank. Method according to claim 4, characterized in that that the solder material, the elements tin, silver, zinc and / or copper includes. Method according to one of the preceding claims, characterized in that the component blank by forging made of steel and the bearing ring immediately after forging inserted into the still-forged component blank becomes. Method according to one of the preceding claims, characterized in that the bearing component is a connecting rod and the bearing ring is pressed into the connecting rod eye of the connecting rod blank and the connecting rod eye shrinks on cooling on the bearing ring. Method according to one of the preceding claims, characterized in that the component blank during insertion of the bearing ring has a temperature of more than 400 ° C. Method according to claim 4, characterized in that that the component blank when inserting the bearing ring a Temperature of more than 1150 ° C has. Method according to one of the preceding claims, characterized in that the bearing ring is pressed into the bearing eye becomes. Method according to one of the preceding claims, characterized in that during and after insertion of the bearing ring in the bearing eye of the component blank a substance bond done by sintering or diffusion. Method according to one of the preceding claims, characterized in that the component blank of a forged steel exists and is transformed by a forging process. Method according to one of the preceding claims, characterized in that the component blank made of austempered Ductile Iron (ADI) exists and the insertion of the bearing ring immediately after the annealing of the component blank. Method according to one of the preceding claims, characterized characterized in that a fracture separation of the bearing eye after insertion of the Bearing ring takes place. Method according to one of the preceding claims, characterized in that the bearing ring a predetermined breaking point having. Method according to one of the preceding claims, characterized in that the bearing ring of two or more Cups is composed. Method according to one of the preceding claims, characterized in that the component is a connecting rod ( 2 ) is for an internal combustion engine.