DE102017119964A1 - Bearing device, planetary gear with a bearing device and method for producing and mounting a planetary bolt - Google Patents

Abstract

The invention relates to a bearing device, with which at least one machine part is supported by means of at least one bearing pin via at least two support bearings radially in a carrier, wherein:
- The bearing pin is made of a steel,
- The bearing pin has a bolt surface which extends axially rectified with a longitudinal axis of the bearing pin and at least by a central portion and a first end portion and a second end portion defined bolt surface,
the middle section is formed axially between the two end sections,
the machine part is mounted radially transversely to the longitudinal axis, on the middle section,
the bearing pin is radially supported with the first end portion in the first support bearing and is radially supported with the second end portion in the second support bearing,
- At least the central portion has a surface hardening resulting from a boundary layer.
The invention also relates to a planetary gear with such a bearing device and a method for producing a planetary pin.

Description

Field of the invention

• - der Lagerbolzen aus einem Stahl gebildet ist,
• - der Lagerbolzen eine Bolzenoberfläche aufweist, welche axial mit einer Längsachse des Lagerbolzens gleichgerichtet verläuft sowie zumindest durch einen Mittelabschnitt und einen ersten Endabschnitt und einen zweiten Endabschnitt definierte Bolzenoberfläche aufweist,
• - der Mittelabschnitt axial zwischen den beiden Endabschnitten ausgebildet ist,
• - das Maschinenteil radial quer zur Längsachse, auf dem Mittelabschnitt gelagert ist,
• - der Lagerbolzen mit dem ersten Endabschnitt in dem ersten Stützlager radial abgestützt und mit dem zweiten Endabschnitt in dem zweiten Stützlager radial abgestützt ist,
• - zumindest der Mittelabschnitt eine aus einer Oberflächenhärtung resultierende Randschicht aufweist.

The invention relates to a bearing device with which at least one machine part is supported by at least one bearing pin via at least two support bearings radially in a carrier, wherein:

• - The bearing pin is made of a steel,
• - The bearing pin has a bolt surface which extends axially rectified with a longitudinal axis of the bearing pin and at least by a central portion and a first end portion and a second end portion defined bolt surface,
• the middle section is formed axially between the two end sections,
• the machine part is mounted radially transversely to the longitudinal axis, on the middle section,
• the bearing pin is radially supported with the first end portion in the first support bearing and is radially supported with the second end portion in the second support bearing,
• - At least the central portion has a surface hardening resulting from a boundary layer.

The invention also relates to a planetary gear with such a bearing device and a method for producing a planetary pin.

Background of the invention

Bearing devices of the genus are used for example in valve trains of internal combustion engines and planetary gearboxes of the motor vehicle transmission. Often the machine parts are mounted by means of rolling bearings on the bearing pin. Accordingly, the bearing bolts have hardened surfaces of rolling bearings. The bearing pins are made of steels suitable for rolling bearings and either through hardened or surface hardened. The structure of the steel is hard after hardening to the core of the material of the bearing pin. Surface hardened components are provided with a hardened surface layer, which has the necessary surface hardness. Surface hardening includes processes such as flame hardening, induction hardening, laser beam and electron beam hardening. Furthermore, there are use and nitriding. During use and nitriding, a structure is generated under heat by diffusion of carbon and nitrogen atoms into the surface layer, which increases the strength in the edge region of the workpiece surface. The hardened bearing pins are inserted into the carrier and secured there by caulking in the carrier. When caulking the end of the bearing pin is plastically displaced by embossing material so that the plastically displaced material forms a positive connection with the carrier. About the positive connection, the bearing pins are axially secured in the carrier.

There are also known applications in which the hardened steel is embossed to produce such a positive locking. Due to the hardness of the material, however, such a method and the resilience of such positive locking are limited. Therefore, as in DE 102 38 252 B4 is described in more detail, subjected to the ends of through hardened bearing pin before caulking the front side of a soft annealing. During soft annealing, the precipitates of cementite or perlite present in the structure of hardened steel are reduced, ie "softened" for the subsequent plastic deformation during caulking.

Out DE 102 38 252B4 Surface hardened bearing bolts are also known in which the edge layer at the end sections has softened after caulking for the caulking. The planet carriers of planetary gears in vehicles are, as in DE 10 2010 019 976 B4 very often exposed to high loads, which are caused by high torques and helical gears. The planet pins are taken with their end portions in support bearings of support portions of the planet carrier. At least one planet gear is preferably mounted with a needle bearing or slidably on the respective planet pins. The sections are made of sheet metal and deform due to the high loads elastic. The support bearings of the planet pins are extremely stressed due to these deformations.

The position fuses generally known in the art by caulking come off and the planet pins begin to move uncontrollably in the respective storage device. The same applies to the storage devices, such as these DE 195 34 791 A1 are known. In these storage devices, the end portions of the planet pins are provided with conical countersinks, which are determined by radial expansion in the holes of the planet carrier, ie with a kind of non-positive connection from the inside out.

Description of the invention

The object of the invention is therefore to provide a storage device with which the aforementioned problems are eliminated. Particular object of the invention is to make storage devices for planetary pins in planetary gears so that the support bearings and positional securing the Planet bolts also withstand the high deformations of the planet carrier.

This object is achieved by the subject matter of claim 1 and further dependent of claim 1 claims.

According to the invention, the bearing pin is axially secured to one or more support bearings by at least one collar so that it can not migrate axially out of the carrier. The collar portion on which the collar is formed is integrally-einmaterialig formed from the steel of the bearing pin and thus not separable integrally with the bearing pin. The collar is preferably a circumferential, interrupted or segmented edge of the bearing pin. The collar is at least partially radially out of the bearing pin and is the carrier at least partially axially opposite so that the bearing pin is supported on the carrier at least in an axial direction on the collar.

The collar portion on which the collar is formed, closes axially, d. h., Towards the rectified with the longitudinal axis, the hardened edge layer of the central portion, wherein the hardened edge layer terminates in an end portion and runs out. In other words, the steel of the collar portion is not hardened and unaffected by the surface hardening of the billet blank.

The radial thickness of the surface layer is dependent on the loads of the bearing pin. It has a radial thickness which is constant at least longitudinally in the middle section and becomes radially thinner in an end section adjoining the middle section and runs out to the end of the central section as far as the collar section. The collar portion is formed at the end of the planetary bolt.

Surface hardening is a surface hardening. Examples of such methods are inductive, flame, insert and nitriding as well as laser and electron beam curing. Hardening in general means, on the one hand, a heat treatment consisting of austenitizing and cooling under conditions such that the hardness of the material is usually increased by more or less complete transformation of the austenite into martensite. On the other hand, curing can be subdivided into thermal or thermochemical processes.

Surface hardening specifically influences a certain depth of the material by hardening technology.

Between the hardened area and the uninfluenced material arises the so-called "transition zone". As a result of this surface hardening only one outer layer, so the edge layer is cured. Surface hardening generates a martensitic structure in the surface layer. In essence, the composition of the steel and the hardness and toughness of the starting material remain before hardening.

Thermal processes include, for example, the inductive hardening process. In thermal processes, the chemical composition of the starting material is not changed during the heat treatment. This requires a minimum carbon content of the steel.

In contrast, in thermochemical processes, the workpiece is first exposed to a chemical atmosphere containing carbon and / or nitrogen, so that carbon and / or nitrogen diffuses into the boundary layer. Examples of the thermochemical processes are case hardening, nitriding or carbonitriding. In case hardening, the surface layer of the workpiece is "carburized", that is, it diffuses carbon into the surface layer. During nitriding, nitrogen diffuses and carbonitriding uses an atmosphere mixed with carbon and nitrogen.

The tempering is followed optionally or forcibly by a tempering process for reducing residual stresses in order to increase the toughness of the workpiece.

It was initially in the chapter "Background of the Invention" on DE 102 38 252B4 directed. The bearing pin described therein, as with the 5a and 5b induction hardened (referred to herein as high frequency quenching), but only at a central portion. At both ends of the bearing bolt end portions remain that should not be hardened. In fact, however, the structure of the respective end portion is influenced by the heat input at the central portion and harder than the starting material of the billet blank. The core hardness, ie, the hardness of the starting material is approximately achieved only at the end face of the respective end portion, as that for the skilled person with reference to the in 5b shown hardness curve is traceable. For the middle section ( 2c ), which was exposed directly to the hardening temperatures, results in a surface hardness of at least 650HV. The hardness decreases already starting in the middle section towards the respective end of the bearing pin, but is also above the hardness of the starting material at the end of the bearing pin.

The in DE 102 38 252B4 illustrated bearing pin is secured by simple plastic notching the respective end face. such Methods are typical in the prior art and are sufficient for the illustrated application, but not for securing bearing pins in highly stressed bearing devices. As soon as the material is to be plastically deformed in such end sections influenced by the hardening beyond simple notching, there is the risk that the material will crack or crack due to the structure being too hard. This can lead to premature failure of the storage devices.

According to the invention, a transition zone, in which the influence of the introduced heat also has effects on the hardness of the microstructure, placed in front of the collar portion, which is to be reshaped for axial securing. The hardened edge layer ends with certainty in the end section. The material of the collar portion provided for the plastic shaping of the collar remains soft. Cracks and cracks are avoided. A secure hold of the respective bearing pin is guaranteed.

An embodiment of the invention provides that the bearing pin on both sides at the end in each case the collar portion and collar according to the invention, so that the bearing pin is axially on both sides securely supported on the support.

The bearing pin preferably has the hardness of the starting material used to produce the bearing pin on the collar portion and on the collar. This is particularly advantageous if good deformable steel is to be used for the production of the bearing pin. Such steels generally have a low carbon content for curing, so that often thermochemical heat treatments are provided. The middle section has, in particular in the case of the use of rolling bearings for the storage of the machine part, a hardness of min. 620 HV. The numerical value is only an example and relates to the hardness test according to the known Vickers method, in which a diamond pyramid with a defined opening angle is pressed into the workpiece under a defined test force and the impression is subsequently measured and compared with references.

The invention is preferably intended for use in planetary gearboxes. The planet pins preferably each have two of the collars. The planetary pin is formed from a billet blank whose steel is partially provided with the edge layer. A first microstructure of the steel of the planetary bolt corresponds to a microstructure of the raw material used for the billet blank. The edge layer has a second, for example martensitic, microstructure changed by the heat treatment. The hardness of the steel in the surface layer is greater than the hardness of the microstructure in the core of the walls of the planetary bolt. The steel in the collar is at least partially formed from the billet blank and thereby has completely the first microstructure and the first hardness of the starting material.

In addition, the respective planet pins, as an embodiment of the invention provides, provided with at least one projection which engages positively in the respective first support portion and second support portion. The respective planet pins is secured in this way relative to the planet carrier by means of the projections against rotation about its longitudinal axis on the planet carrier. The longitudinal axis of the planetary pin is its axis of symmetry lies on the axis of rotation of the planet pin mounted on the planet pin. The projections are preferably formed by subsequent embossing of the collar or during plastic forming of the collar in these integrated projections. By means of a stamping tool, a partial deformation of the material to be embossed for the projections is made. As an embossing tool here an embossing die or an embossing roll can be used. Due to the targeted pressure effect of the respective embossing tool, it comes on the back of the embossed portion to formations. The formations engage in depressions on the planet carrier and form a positive connection. The recesses are formed, for example, during embossing of the respective protrusion, in that the embossing stamp plastically pushes the material out of the planetary bolt and at the same time into the support section through plastic displacement of material from the support section.

• - Herstellen eines Bolzenrohlings aus einem nicht gehärtetem oder nicht eingesetzten bzw. aufgekohlten oder nitrierten Ausgangsmaterial des Stahls, zum Beispiel aus einem Einsatzstahl 16 MnCr5 alternativ aus einem Wälzlagerstahl wie 100Cr6.
• - Erzeugen der Randschicht an den Bolzenrohling durch partielles thermisches oder thermochemisches Randschichthärten so, dass mindestens ein Kragenabschnitt an dem Bolzenrohling verbleibt. Es ergibt sich, dass die Härte des Stahls in der Randschicht größer ist als die Härte des Ausgangsmaterials, wobei der Stahl des Kragenabschnitts gegenüber der Gefügestruktur und Härte des für den Bolzenrohling verwendeten Ausgangsmaterials unveränderte erste Gefügestruktur und erste Härte aufweisen soll. Das wird durch gezielte Steuerung des Wärmeeintrags bzw. festgelegte Diffusionszonen und/oder Abdecken nicht zu härtender Bereiche erzielt.

The invention also provides a method for producing a bolt blank for a planetary pin of a planetary gear, which is characterized by the following steps:

• - Producing a billet blank from a non-hardened or unused or carburized or nitrided starting material of the steel, for example from a case hardening steel 16 MnCr5 alternatively from a bearing steel such as 100Cr6.
• - Producing the edge layer to the bolt blank by partial thermal or thermochemical surface hardening so that at least one collar portion remains on the bolt blank. It turns out that the hardness of the steel in the surface layer is greater than the hardness of the starting material, wherein the steel of the collar portion compared to the microstructure and hardness of the starting material used for the billet blank unchanged initial microstructure and first hardness should have. This is achieved by targeted control of the heat input or specified diffusion zones and / or covering non-hardened areas.

• - Einsetzen des Bolzenrohlings in den Planetenträger, wobei der zumindest eine Kragenabschnitt an zumindest einem der Stützlager axial über den jeweiligen Trägerabschnitt hinaus steht,
• - Herstellen des Planetenbolzens aus dem Bolzenrohling durch Formen des mindestens einen Kragenabschnitts, wobei beim Umformen endseitig des Bolzenrohlings der über den Trägerabschnitt hinaus stehende Stahl des mindestens einen Kragenabschnitts zumindest durch teilweise plastische Materialverformung zu dem Kragen geformt wird.

The collar portion is left soft in the first place and does not need to be tempered. This saves time and money. Subsequently, the respective planetary pin is inserted into the planetary gear or the planetary gear is mounted by inserting the bolts, but it is assumed that the mounting of the bearings and the planetary gears are also integrated into the assembly process. This results in the following inventive method for producing and mounting a planetary pin in a planetary drive:

• Inserting the bolt blank into the planetary carrier, wherein the at least one collar section projects axially beyond the respective carrier section on at least one of the support bearings,
• - Produce the planetary bolt from the bolt blank by forming the at least one collar portion, wherein during forming end of the bolt blank of standing beyond the support portion steel of the at least one collar portion is formed at least partially plastic material deformation to the collar.

The method also provides for the installation of planet pins, which have a collar on both sides. It is conceivable that one of the collar is already formed before the assembly of the blank of the planetary bolt or possibly also machined. Alternatively, both collars are formed only when the respective bolt blank is fitted to both support bearings in the carrier. The fitting installation of the planetary gear is secured. Necessary games or press dressings can be advantageously integrated into the operation of the plastic molding of the collar. A secure fit of the planet pins in the planet carrier is guaranteed.

list of figures

• 1 - Die Lagervorrichtung 11, mit der mehrere Maschinenteile 17 mittels Lagerbolzen 18 über zwei Stützlager 5 und 6 in einem Träger 7 abgestützt sind, ist als Planetengetriebe 1 ausgeführt. Die Maschinenteile sind als Planetenräder 10 und 12 ausgeführt. Der Träger 7 ist ein mehrteiliger Planetenträger 8. Das Planetengetriebe 1 ist in einem Halbschnitt längs entlang der zentralen Achse 2 Planetengetriebes 1 dargestellt, so dass sich auch eine Schnittdarstellung entlang der Längsachse 4 eines Planetenbolzens 3 durch ein Planetenrad 10 sowie durch zwei Stützlager 5 und 6 eines Ausführungsbeispiels der erfindungsgemäßen Lagervorrichtung 11 ergibt.
• 2 zeigt ein Detail des Planetengetriebes 1 mit der Lagervorrichtung 11 im vormontierten Zustand, in dem ein Bolzenrohling 3a des Planetenbolzens 3 in die Stützlager 5 und 6 eingepasst ist, in dem Längsschnitt nach 1.
• 3 zeigt das Detail nach 2, jedoch nach Montage des Planetenbolzens mit einem erfindungsgemäßen Verfahren.

The invention will be explained in more detail with reference to embodiments.

• 1 - The storage device 11 , with the several machine parts 17 by means of bearing bolts 18 over two support bearings 5 and 6 in a carrier 7 are supported as a planetary gear 1 executed. The machine parts are called planetary gears 10 and 12 executed. The carrier 7 is a multipart planet carrier 8th , The planetary gear 1 is in a half section along the central axis 2 planetary gear 1 represented, so that also a sectional view along the longitudinal axis 4 a planetary bolt 3 through a planetary gear 10 as well as two support bearings 5 and 6 an embodiment of the storage device according to the invention 11 results.
• 2 shows a detail of the planetary gear 1 with the storage device 11 in pre-assembled condition, in which a bolt blank 3a of the planetary bolt 3 in the support camp 5 and 6 is fitted, in the longitudinal section to 1 ,
• 3 shows the detail 2 but after assembly of the planetary bolt with a method according to the invention.

1 - the planetary gear 1 is designed as a spur gear differential. It consists of a planet carrier 8th , a drive wheel 9 , two sets of planet wheels 10 and 12 as well as sun wheels 13 and 14 , The multi-part carrier 7 is as a planet carrier 8th or differential basket.

Due to the graphic representation is from the planetary gears 10 and 12 only one planetary gear 10 visible, noticeable. One of the planet wheels 12 of the other planetary gear set is in the representation by the planetary gear lying in the foreground 10 hidden and indicated only by a dashed line. Each planetary wheel of each set sits around its own axis of rotation 15 rotatably mounted on its own planetary bolt 3 , The respective position device 11 of the respective planetary bolt 3 is from the support camps 5 and 6 educated.

The planetary pin 3 sits on the left side in a cylindrical bore of a support bearing 5 in the vehicle section 8a and in the picture right side in a cylindrical bore of the support bearing 6 in the vehicle section 8b , The respective support bearings 5 and 6 form radial supports.

Radial is transverse to the course of the central axis 2 or to the axes of rotation in 15. Axial is with the axes 2 and 15 rectified.

The respective planet pin 3 is on each support bearing, each with a collar 16 Mistake. The respective collar 16 is at the end of the planetary bolt 3 formed circumferentially like a funnel-shaped edge and is radially above the surface of the cylindrical planetary pin 3 as well as the edge of the cylindrical bore.

The collar 16 is extended radially so far that it is the respective support section 8a respectively. 8b axially on the outside of the carrier 8th opposite. The planetary pin 3 is characterized in both axial directions on the carrier 8th secured. In addition, each collar has 16 as anti-twist device around the axis of rotation 15 at least one projection 19 on which after mounting the planet pins 3 is generated in each case by embossing and in positive engagement with the respective support section 8a respectively. 8b stands.

2 - When mounting the planetary gear 1 become bolt blanks 3a through the respective planet gears 10 respectively. 12 passed and into the cylindrical holes of the support bearing 5 respectively. 6 fitted. Each of the bolt blanks 3a is formed as a hollow cylinder, has a central portion 20 , at each end of the middle section 20 an end section 21 as well as at each end of the planetary bolt 3 a collar section 22 on. Such bolt blanks 3a are produced for example by machining or produced by extrusion. The starting material used to make the billet blanks is uncured steel, in this case bearing steel 100 Cr6. The wall thicknesses D of the middle section 20 and the respective end section 21 are greater than the wall thicknesses d of the collar sections 22 , The bolt blanks 3a be before mounting in the planet carrier 8th hardened and tempered. Then show the bolt blanks 3a at the middle section 20 one edge layer each 23 the depth T on. Subject to a transition zone between the surface layer and the other material, the steel of the billet blank 3a , except in the outer layer 23 , the microstructure of the starting material. The structure of the surface layer 23 results in this case from inductive hardening. The hardening depth T of the surface layer decreases in the end section 21 Finally, it goes over to the end in the hardness of the starting material, so that the collar section 22 having the hardness of the starting material.

3 - after fitting the bolt blanks 3a in the planet carrier 8th become the planet pins 3 by plastic widening of the soft collar portion 22 in the respective collar 16 produced and at the same time thereby at the respective support bearing 5 respectively. 6 secured in an axial direction. In this case, the material of the collar portion 22 into a chamfer 24 displaced, in which the finished collar 16 at the respective support section 8a respectively. 8b axially supported.

LIST OF REFERENCE NUMBERS

1

planetary gear

2

Central axis

3

planet shaft

3a

bolt blank

4

longitudinal axis

5

support bearings

6

support bearings

7

carrier

8th

planet carrier

8a

support section

8b

support section

9

drive wheel

10

planet

11

bearing device

12

planet

13

sun

14

sun

15

axis of rotation

16

collar

17

machinery

18

bearing bolt

19

head Start

20

midsection

21

end

22

collar section

23

boundary layer

24

chamfer

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

• DE 10238252 B4 [0004, 0005, 0018, 0019]
• DE 102010019976 B4 [0005]
• DE 19534791 A1 [0006]

Claims (12)

Bearing device (11), with the at least one machine part (17) by means of at least one bearing pin (18) via at least two support bearings (5, 6) radially in a carrier (7) is supported, wherein: - the bearing pin (18) made of a steel the bearing pin (18) has a pin surface which runs axially rectified with a longitudinal axis (4) of the bearing pin (18) and at least by a middle section (20) and a first end section (21) and a second end section (21). having defined pin surface, - the middle section (20) is formed axially between the two end sections (21), - the machine section (17) is mounted radially transversely to the longitudinal axis (4), on the central section (20), - the bearing pin (18) with the first end portion (21) in the first support bearing (5) radially supported and with the second end portion (21) in the second support bearing (6) is radially supported, - at least the central portion (20) one of a Oberf - characterized by at least one collar portion (22), wherein: - the collar portion (22) is einstückig einmaterialig of the steel of the bearing pin (18) and axially at least in one of the end portions (21) continues on the bearing pin (18) and at the end of the bearing pin (18) has a collar (16), - the collar (16) is at least partially radially out of the end of the bearing pin (18) and the support (7) on the support bearing (5, 6) at least partially so axially opposite, that the bearing pin (18) at least in an axial direction on the collar (16) on the support (7) is supported, - the edge layer (23) axially rectified with the longitudinal axis ( 4) beyond the central portion (20) into which the at least one end portion (21) extends, the edge layer (23) terminating in the end portion (21), - the steel of the collar portion (22) is not hardened, whereby the steel is in least of the collar portion (22) is unaffected by the surface hardening. Storage device according to Claim 1 characterized in that the edge layer (23) has a radial thickness (T) which is constant at least longitudinally along the central portion (20) and the marginal layer (23) in at least one end portion (21) axially towards the collar portion (22 ) continuously decreasing in the radial direction becomes thinner and ends in the at least one end portion (21). Storage device according to Claim 1 , characterized in that the edge layer (23) at least partially extends over both end portions (21) and that the two end portions (21) each have a collar portion (22) connected to the collar (16), wherein the collar (16) on the carrier (7) are axially opposite each other. Storage device according to Claim 2 or 3 , characterized in that all further of the edge layer (23) adjoining areas of the steel on the collar (16) are not hardened. Storage device according to Claim 2 or 3 , characterized in that the surface hardness of the surface layer (23) in the central portion (20) on the surface at least 620 HV. Planetary gear (1) with planetary gears (10, 12), planet pins (3) and a planet carrier (8), with the bearing device (11) according to Claim 1 in which the machine parts (17) are the planetary gears (10, 12) rotatably mounted on the middle section (20) about a rotation axis (15), the planet pins (3) are the bearing pins (18) and the carrier (7) is a planetary carrier (8), wherein the rotation axis (15) lies on the longitudinal axis (4) of the bearing bolts. Planetary gear to Claim 6 , characterized in that the respective planet pin (3) has two of the collars (16), each of the end sections (21) each one of the collar sections (22) connects, and that the first support bearing (5) on a first support portion ( 8a) of the planetary carrier (8) and the second support bearing (6) on a second support portion (8b) of the planet carrier (8) is formed, wherein the planet pins (3) on the first support bearing (5) by means of a first collar (16) axially is supported in a first direction and by means of a second collar (16) on the second support bearing (6) axially in a direction opposite to the first direction second direction. Planetary gear to Claim 7 , characterized in that the respective collar (16) is provided with at least one projection (19) which engages positively in the respective first carrier portion (8a) and second carrier portion (8b), wherein the planet pins (3) relative to the planet carrier ( 8) by means of the projections (19) against rotation about the longitudinal axis (4) on the planet carrier (8) is secured. Planetary gear (1) with planetary gears (10, 12), planet pins (3) and at least one planet carrier (8), wherein the planet pins (3) in each case at least two support bearings (5, 6) on the planet carrier (8) radially and axially are supported, the planetary gears (10, 12) each about an axially aligned rotation axis (15) rotatable at least radially, ie transversely to the axis of rotation (15) on a hardened edge layer (23) of a planetary pin (3) are mounted from steel and wherein at least one of the planet pins (3) is formed from a bolt blank (3a) whose steel is partially provided with the edge layer (23), wherein a first microstructure of the steel of the planetary bolt (3) of a microstructure corresponds to the starting material used for the billet blank (3a) and the edge layer (23) has a second microstructure, which is changed relative to the first microstructure such that the hardness of the steel in the edge layer (23) is greater than a first hardness of the first microstructure and wherein the planet pin (3) has at least one end integrally formed with the planet pin (3) and axially laterally of the edge layer (23) radially beyond the edge layer (23) standing collar (16) and at least one of the support bearing ( 5, 6) is supported axially by means of the collar (16), wherein the steel in the collar (16) ausfor at least partially from the bolt blank (3a) mt is and has completely the first microstructure and the first hardness of the starting material. A method for producing a bolt blank (3a) for a planetary pin (3) of a planetary gear (1) according to Claim 6 or 9 characterized by the following steps: - producing a billet blank (3a from a starting material of the steel, - producing the marginal layer (23) on the billet blank (3a) by partial surface hardening so that at least one collar portion (22) remains on the billet blank and so that the hardness of the steel in the boundary layer (23) is greater than a hardness of the starting material, the steel of the collar section (22) having an unchanged first microstructure and first hardness relative to the microstructure and hardness of the starting material used for the billet blank (3a). Method for producing and mounting a planetary bolt (3) in a planetary drive (1) according to Claim 6 or 9 characterized by the following steps: inserting the bolt blank (3a) into the planetary carrier (8), wherein the at least one collar portion (22) projects axially beyond the respective carrier portion (8a, 8b) on at least one of the support bearings (5); Producing the planetary bolt (3) from the bolt blank (3a) by forming the at least one collar portion (22), wherein upon forming the end of the bolt blank (3a) the steel of the at least one collar portion (22) protruding beyond the support portion (8a, 8b) is formed at least by partial plastic deformation of the material to the collar (16). Method according to Claim 11 , characterized in that the hardness of the starting material in generating the edge layer (23) on two collar portions (22) is maintained and that the bolt blank (3a) is inserted into the planet carrier (8), that in each case a collar portion (22) axially over the respective support portion (8a, 8b) is also out and in each case to a collar (16) is formed.

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