DE102020202288A1 - Planetary gear set - Google Patents

Abstract

A planetary gear set (1) is proposed, comprising a planet carrier (3), a ring gear (4) and a sun gear (2), which is non-rotatably connected to an adjacent component (7), the planet carrier (3) via a first Axial bearing (10) is mounted on the sun gear (2) and via a second axial bearing (11) on the component (7), the first and second axial bearings (10, 11) being designed as sliding bearings, each of which is a hollow cylindrical, in the assembled state axially extending section (12) and a disk-shaped section (13) which extends radially in the assembled state and forms a sliding disk, the axially and radially extending section (12, 13) each radially and / or axially and / or over the circumference have introduced contours (14, 15) which are used to deliver oil and to lubricate the sliding surfaces of the sliding washers.

Description

The present invention relates to a planetary gear set comprising a planet carrier, a ring gear and a sun gear, which is non-rotatably connected to an adjacent component, wherein the planet carrier is mounted on a first axial bearing on the sun gear and a second axial bearing on the component, according to the The invention also relates to a transmission for a motor vehicle comprising at least one planetary gear set according to the invention.

It is known from the prior art to use axial roller bearings, in particular axial needle roller bearings, for mounting two adjacent components with differential speeds in a planetary gear set, with disks being used as the raceway. As a rule, the disks serving as a raceway are fixed to one of the adjacent components for the purpose of securing them from being lost, whereby in such axial rolling bearings, due to the spacing between the rolling elements, a flow of oil is possible. A disadvantage of such axial roller bearings is that they require a large amount of installation space at high manufacturing costs.

From the DE 10 2007 037 531 A1 a planetary stage is known, comprising a sun gear, a planet carrier and a ring gear, the planet carrier leading rotatably mounted several planet gears, which are in tooth engagement with both the sun gear and the ring gear and is mounted via axial bearings in the form of roller bearings.

In order to enable a compact design, it is advantageous to design the axial bearings as slide bearings, in particular as slide disks, in order to support two adjacent components with differential speeds in a planetary gear set. However, this results in the fact that no oil flow is possible, since the neighboring components usually lie flat on a sliding washer.

From the DE 37 21 384 C2 an axial sliding bearing element is known which is designed as an annular or partially annular thrust washer with a sliding surface and a back surface. In the known axial sliding bearing element, at least one embossed groove extending in the circumferential direction and over at least parts of the circumference is provided in at least one of the two surfaces of the thrust washer, through which a more precise flat surface shape is created on the sliding surface and on the back surface and the axial sliding bearing element against deformation and loss of the flat surface shape is better stabilized. According to a further development, it can be provided that the groove running in the circumferential direction of the thrust washer intersects with functional grooves made in the sliding surface, which can be designed as lubricant grooves, for example.

The present invention is based on the object of specifying a planetary gear set comprising a planet carrier, a ring gear and a sun gear, which is non-rotatably connected to an adjacent component, the planet carrier being mounted on the sun gear via a first axial bearing and on the component via a second axial bearing .

This object is achieved by the features of claim 1. Further embodiments and advantages according to the invention emerge from the subclaims. A transmission for a motor vehicle comprising at least one planetary gear set according to the invention is the subject of patent claim 8.

Accordingly, a planetary gear set is proposed, comprising a planet carrier, a ring gear and a sun gear, which is non-rotatably connected to an adjacent component the second axial bearing are designed as plain bearings, each comprising a hollow cylindrical section that runs axially in the assembled state and a disk-shaped section that runs radially in the assembled state and forms a sliding disk, the axially and the radial section each having introduced contours that correspond to the Oil production and the oiling of the sliding surfaces of the sliding washers are used. The adjacent component can be a shaft, for example a hollow shaft.

The contours can be designed as embossed grooves, for example. Alternatively, the contours can be produced by machining. The contours can be introduced axially and / or radially and / or over the circumference of the respective section.

According to a further development of the invention, the first and / or the second axial bearing has at least one further section which runs radially and / or axially in the assembled state, which has contours introduced radially and / or axially and / or over the circumference and an oil supply through two adjacent ones Components without a differential speed for oiling the sliding surface of the sliding washer and subsequent points possible.

The sections of the axial bearings can be designed as components made of steel, for example.

The planetary gear set can be designed as a minus or a plus planetary gear set. A As is known, simple minus planetary gear set comprises a sun gear, a ring gear and a web on which planet gears are rotatably mounted, each of which meshes with the sun gear and ring gear. As a result, when the web is held in place, the ring gear has a direction of rotation opposite to that of the sun gear. In contrast, a simple plus planetary gear set comprises a sun gear, a ring gear and a web on which inner and outer planet gears are rotatably mounted, all inner planet gears meshing with the sun gear and all outer planet gears meshing with the ring gear, each inner planet gear having an outer one Planet gear meshes. As a result, when the web is held in place, the ring gear has the same direction of rotation as the sun gear and a positive stationary gear ratio results.

The concept according to the invention achieves a compact design while at the same time ensuring the lubrication of the sliding surfaces and the targeted oil transport to the sliding points or to the surrounding components.

• 1: Eine schematische Schnittansicht eines Teiles eines gemäß einer ersten Ausgestaltung der Erfindung ausgeführten Planetenradsatzes;
• 2: Eine schematische Schnittansicht eines Teiles eines gemäß einer zweiten Ausgestaltung der Erfindung ausgeführten Planetenradsatzes; und
• 3: Eine schematische Draufsicht eines eine Gleitscheibe bildenden Abschnitts einer Gleitlagerung eines erfindungsgemäß ausgeführten Planetenradsatzes.

The invention is explained in more detail below with reference to the accompanying figures using a minus planetary gear set by way of example. The general structure and the mode of operation of planetary gear sets are very well known to the person skilled in the art, so that the features that are important for the present invention are described in detail below. Show it:

• 1 : A schematic sectional view of part of a planetary gear set designed according to a first embodiment of the invention;
• 2 : A schematic sectional view of part of a planetary gear set designed according to a second embodiment of the invention; and
• 3 : A schematic plan view of a sliding disk forming section of a sliding bearing of a planetary gear set designed according to the invention.

In 1 is part of a negative planetary gear set integrated in a transmission, in particular in an automatic transmission of a motor vehicle 1 shown, which is a sun gear 2 , a planet carrier 3 and a ring gear 4th having; with the reference number 5 is one of the planetary gears referred to, which is on a planetary pin 6th is rotatably mounted. The planet gears 5 each stand with the sun gear 2 , as well as the ring gear 4th in engagement.

In the example shown, the sun gear is 2 of the planetary gear set 1 via a driving gear 8th with an adjacent wave 7th , which is designed as a hollow shaft, rotatably connected.

The planet carrier 3 has a radially inwardly extending collar 9 on, by means of which he axially between the sun gear 2 and the hollow shaft 7th is led. The storage of the planet carrier 3 takes place via a first and a second axial bearing 10 , 11 , the first thrust bearing 10 between the sun gear 2 and the federal government 9 of the planet carrier 3 and the second thrust bearing 11 between the federal government 9 of the planet carrier 3 and the hollow shaft 7th is arranged.

According to the invention, the first and second axial bearings 10 , 11 designed as plain bearings, each having a hollow cylindrical section that extends axially in the assembled state 12th and a disk-shaped section which extends radially in the assembled state and forms a sliding disk 13th , include.

For oil delivery and lubrication of the sliding surfaces of the sliding washers of the axial bearings 10 , 11 have the axially and the radial section of the axial bearing 10 , 11 each radially and / or axially introduced contours. Exemplary contours of a radially extending, disk-shaped section forming a sliding disk 13th are the subject of 3 . In 1 becomes the direction of flow of the oil for lubricating the first axial bearing 10 by the arrow 18th illustrated. As can be seen from the figure, the inventive design of the axial bearing 10 the following components are also supplied with oil.

Referring to 3 has the portion forming a sliding washer 13th of a thrust bearing radially extending contours, for example grooves 15th for oil production and for oiling the sliding surface, which are preferably distributed over the circumference. Furthermore, in the example shown, the section forming a sliding washer has 13th in the circumferential direction and over at least parts of the circumference extending contours, for example grooves 14th that serve to lubricate the sliding surface.

The subject of 2 differs from the design according to 1 in that the first axial bearing 10 another section running radially in the assembled state 16 which has contours introduced radially and / or axially and / or over the circumference and an oil supply through two adjacent components without a differential speed, namely through the sun gear 2 and the hollow shaft 7th for oiling the sliding surface of the sliding washer of the axial bearing 10 and subsequent positions.

The in 2 The example shown is viewed axially in front of the further section which extends radially in the assembled state 16 an axially extending section 17th provided, the radially and / or axially and / or over the circumference introduced contours has and is used for oil production. In 2 becomes the direction of flow of the oil for lubricating the first axial bearing 10 by the arrow 19th illustrated.

List of reference symbols

1

Planetary gear set

2

Sun gear

3

Planet carrier

4th

Ring gear

5

Planetary gear

6th

Planet gear bolts

7th

Hollow shaft

8th

Driving gearing

9

Federation

10

first axial bearing

11

second axial bearing

12th

axially extending section of the axial bearing 10 , 11

13th

radial section of the axial bearing 10 , 11

14th

Groove

15th

Groove

16

another radial section of the axial bearing 10

17th

another axially extending section of the axial bearing 10

18th

Direction of oil flow

19th

Direction of oil flow

QUOTES INCLUDED IN THE DESCRIPTION

This list of the documents listed 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 102007037531 A1 [0003]
• DE 3721384 C2 [0005]

Claims (8)

Planetary gear set (1), comprising a planet carrier (3), a ring gear (4) and a sun gear (2) which is non-rotatably connected to an adjacent component (7), the planet carrier (3) via a first axial bearing (10) is mounted on the sun gear (2) and via a second axial bearing (11) on the component (7), characterized in that the first and second axial bearings (10, 11) are designed as slide bearings, each having a hollow cylindrical, axially in the assembled state extending section (12) and a disk-shaped section (13) which extends radially in the assembled state and forms a sliding disk, the axially and radially extending sections (12, 13) each being introduced radially and / or axially and / or over the circumference Have contours (14, 15) which are used to deliver oil and to lubricate the sliding surfaces of the sliding washers. Planetary gear set (1) Claim 1 , characterized in that the first and / or the second axial bearing (10, 11) has at least one further section (16, 17) which extends radially and / or axially in the assembled state and which extends radially and / or axially and / or over the circumference Has introduced contours and enables oil to be pumped through two adjacent components without a difference in speed for oiling the sliding surface of the sliding disk and subsequent locations. Planetary gear set (1) Claim 1 or 2 , characterized in that the contours are designed as grooves. Planetary gear set (1) according to one of the preceding claims, characterized in that the planet carrier (3) has a radially inwardly extending collar (9), by means of which it is guided axially between the sun gear (2) and the adjacent component (7) is, the first axial bearing (10) between the sun gear (2) and the collar (9) of the planet carrier (3) and the second axial bearing (11) between the collar (9) of the planet carrier (3) and the adjacent component ( 7) is arranged. Planetary gear set (1) according to one of the preceding claims, characterized in that the adjacent component is a shaft (7). Planetary gear set (1) Claim 5 , characterized in that the adjacent component is a hollow shaft (7). Planetary gear set (1) according to one of the preceding claims, characterized in that it is designed as a minus or plus planetary gear set. Transmission for a motor vehicle, comprising at least one planetary gear set (1) according to one of the preceding claims.

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