DE102022002656A1 - Transmission with a first planetary gear stage - Google Patents

Abstract

Transmission with a first planetary gear stage, which has a first sun gear shaft, internal teeth and an epicyclic gear, with the epicyclic gear having a planetary gear into which the cylindrical extension, in particular a pin, of a gear designed as an insert pinion is inserted, the toothing of the planetary gear having a toothing of the first sun gear shaft is in mesh, wherein the teeth of the gear wheel are in mesh with a toothing of the internal gear teeth, wherein the planet wheel is non-rotatably connected to the gear wheel by means of a feather key connection.

Description

The invention relates to a transmission with a first planetary gear stage.

It is generally known that a planetary gear is an epicyclic gear and has an epicyclic gear.

From the U.S. 1,968,604 A a transmission with a planetary gear stage is known as the closest prior art.

From the CN1 06 274 459 A a transmission is also known.

From the CN 1 03 791 033 A a planetary gear is known.

From the US 1 985 964 A an elastic liquid turbine is known.

From the DE 10 2019 006 068 A1 a transmission with at least a first and a second planetary gear stage is known.

From the DE 199 22 651 A1 a wheel drive for a mobile vehicle is known.

A multi-stage planetary gear is known from DD 39 725 A1.

From the DE 10 2014 213 669 A1 a wind power transmission with stepped planet is known.

From the DE 14 30 245 A an outer end of the axle with planetary gear transmission is known.

From the DE 10 2007 034 449 A1 a gear wheel is known.

The invention is therefore based on the object of making a transmission more precise to produce, ie in particular a longer service life for the bearings and toothed parts.

According to the invention, the object is achieved in the transmission according to the features specified in claim 1.

• - wobei das Planetenrad mittels einer Passfederverbindung mit dem Zahnrad drehfest verbunden ist,
• - und/oder wobei der Fortsatz eine Nut, insbesondere Passfedernut, aufweist, in welcher eine Passfeder aufgenommen ist, welche auch in eine Nut des Zahnrades zumindest teilweise hineinragt, insbesondere zur in Umfangsrichtung um die Drehachse des Umlaufrades formschlüssigen Verbindung des Planetenrads mit dem Zahnrad.

Important features of the invention in the transmission with a first planetary gear stage,
which has a first sun gear shaft, internal gearing, in particular of a first ring gear connected to a housing part or a first ring gear designed in one piece with the housing part, and a planetary gear, are that the planetary gear has a planetary gear into which the cylindrical extension, in particular a pin, of a Insertion pinion running gear is inserted,
wherein the toothing of the planet wheel meshes with a toothing of the first sun wheel shaft,
wherein the toothing of the gear meshes with a toothing of the internal toothing,

• - whereby the planetary wheel is non-rotatably connected to the gear wheel by means of a feather key connection,
• - and/or wherein the extension has a groove, in particular a feather keyway, in which a feather key is received, which also projects at least partially into a groove of the gear wheel, in particular for the positive connection of the planetary gear with the gear wheel in the circumferential direction around the axis of rotation of the planetary gear.

The advantage here is that is made possible by an axially bilateral bearing of the planetary wheel and thus a precise alignment of the planetary wheel can be achieved even during operation. This is because the bearing on both sides, which is arranged axially outside the toothing, prevents the planet wheel from tilting. The axially extended design also contributes to this. Because by connecting a plug-in pinion, the planetary gear is axially longer overall. The stabilization is further improved by the large bearing distance. In addition, the different tip circle diameters of the gear and the planetary gear not only allow different transmission ratios, but also contribute to further improved stabilization of the planetary gear. This is because the radial supports provided by the respective toothing, in particular the sun toothing and the internal toothing, are far apart axially and thus enable an additional leverage effect, which strengthens the stabilization.

In an advantageous embodiment, the first planet wheel is thermally shrunk onto the extension and/or thermally joined,
in particular so that the gear is non-positively connected to the first planetary gear. The advantage here is that increased security can be achieved. Because in addition to the form-fitting connection, a non-positive connection is effected.

In an advantageous embodiment, the revolving wheel is slipped onto a planetary pin, the planetary pin being rotatably mounted axially on both sides via a respective bearing accommodated in a planetary carrier of the transmission.
In particular, the bearings are each spaced apart from the gear wheel and/or the planet wheel in the axial direction. The advantage here is that the stability against tilting of the planetary wheel is improved. This enables greater precision.

In an advantageous embodiment, an input shaft of the transmission is rotatably mounted by means of bearings accommodated in a bearing flange of the transmission,
wherein the bearing flange is connected to one or the housing part of the transmission, in particular by means of screws,
wherein the first sun wheel shaft has teeth, in particular splined teeth, which is inserted into a hollow area of the input shaft, in particular hollow shaft section, for the non-rotatable connection of the input shaft to the sun wheel. The advantage here is that the input shaft is non-rotatably connected to the first sun wheel shaft via a gear coupling. In this way, deviations from the ideal position of the input shaft that are introduced on the input side only have a minor effect. The first sun gear shaft thus drives the first gear stage more precisely than if this gear coupling were not present.

In an advantageous embodiment, the first sun gear shaft is rotatably mounted at its end region facing away from the input shaft by means of a bearing which is accommodated in a second sun gear shaft,
in particular wherein the inner ring of the bearing is slipped onto the first sun gear shaft and the outer ring of the bearing is accommodated in the second sun gear shaft. The advantage here is that the coaxial alignment of the two sun wheel shafts allows a coaxial two-stage transmission to be provided, the first being storable in the second sun wheel shaft and thus the most compact possible design can be achieved.

In an advantageous embodiment, the first planetary carrier has internal teeth into which an externally toothed area of the second sun gear shaft is inserted and with which the externally toothed area of the second sun gear shaft engages.
in particular for the non-rotatable connection of the first planet carrier to the second sun gear shaft,
in particular wherein the first planet carrier is rotatably mounted via a bearing accommodated in the housing part. The advantage here is that there is another coupling for tolerance compensation. Thus, despite this, tilting introduced into the first gear stage via the input shaft is still further decoupled from the second gear stage.

In an advantageous embodiment, on the end region of the second sun gear shaft facing away from the input shaft in the axial direction, the second sun gear shaft has teeth which mesh with the teeth of a second planet wheel which is rotatably mounted on a second planet pin, in particular by means of needle bearings.
wherein the second planet bolt is accommodated in a planet carrier,
wherein the toothing of the second planet gear meshes with the internal toothing of a second ring gear. The advantage here is that needle bearings can be used for the planet wheel in the second gear stage. In addition, the ring gear can be designed to be less extended radially than the planetary carrier is designed to be.

In an advantageous embodiment, the second ring gear is non-rotatably connected to a support ring,
in particular in that the support ring is at least partially inserted into the ring gear, the support ring having external teeth which mesh with the internal teeth of the ring gear. The advantage here is that the ring gear is connected to the support ring by means of a toothed coupling, in particular again for decoupling tilting forces, and the support ring can be slipped onto finely machined alignment surfaces which are provided on annular elevations formed on the housing part. The support ring can thus be precisely aligned and holds the second ring gear in the desired position.

In an advantageous embodiment, radially directed, annular elevations, in particular elevations, are formed on the housing part, in particular in relation to the axis of rotation of the second sun gear shaft, which have alignment surfaces running around in the circumferential direction,
onto which the support ring is pushed, in particular for aligning the support ring together with the second ring gear,
in particular wherein the alignment surfaces are spaced from each other in the axial direction. The advantage here is that surfaces which are as finely machined as possible are provided for aligning the support ring and thus the second ring gear, thus enabling high precision during production.

In an advantageous embodiment, the first sun gear shaft is aligned coaxially with the second sun gear shaft. The advantage here is that the transmission can be designed as a coaxial transmission. In addition, the first sun gear shaft can be mounted in the second sun gear shaft, so that the transmission can be made very compact. It is advantageous that the relative speed of the two sun gear shafts is lower than the speed of the first sun gear shaft relative to the housing part.

In an advantageous embodiment, a sleeve is connected to the second planet carrier, which sleeve surrounds the second ring gear radially, in particular with a gap region being formed between the second ring gear and the sleeve. is beneficial in that the ring gear is radially surrounded by the rotating part, namely the sleeve and the second planet carrier.

In an advantageous embodiment, a first bearing is placed with its inner ring on a cylindrical section of the housing part and its outer ring is accommodated in the sleeve
and/or a second bearing, in particular an outer ring of a second bearing, is accommodated in the sleeve, the inner ring of which is slipped onto the support ring,
in particular wherein the support ring has a step against which the second bearing is engaged. The advantage here is that the sleeve is mounted on the two bearings and thus the second planet carrier is mounted on the sleeve. In this way, a large axial distance between the two bearings and the planet carrier can be achieved, so that tilting can be avoided.

The sleeve can be designed as a hollow part, in particular essentially as a hollow cylinder.

In an advantageous embodiment, the support ring is delimited in the axial direction by a shaft nut screwed onto a screw thread applied to the housing part. The advantage here is that a precise and stable alignment of the support ring can be achieved.

In an advantageous embodiment, a shaft sealing ring accommodated in the sleeve seals towards the housing part,
in particular a sealing lip of the shaft sealing ring is in contact with a finely machined surface of the housing part,
in particular a dust seal, in particular a dust seal designed as a V-ring, additionally seals the sleeve towards the housing part. The advantage here is that the shaft sealing ring allows a simple, inexpensive seal.

In an advantageous embodiment, a radial bore running through the sleeve opens into a spatial area adjoining the first and second bearings,
in particular, an axial bore made in the sleeve crossing the radial bore and opening into a spatial area in which the toothing of the second planet wheel is located. The advantage here is that oil can be supplied through the radial bore. During operation, the radial bore is preferably sealed off from the environment with a sealing plug.

Further advantages result from the dependent claims. The invention is not limited to the combination of features of the claims. For the person skilled in the art, there are further meaningful combinations of claims and/or individual claim features and/or features of the description and/or the figures, in particular from the task and/or the task posed by comparison with the prior art.

• In der 1 ist eine Schnittansicht eines erfindungsgemäßen Getriebes dargestellt.
• In der 2 ist ein mehrstückig hergestelltes Umlaufrad des Getriebes in Schrägansicht dargestellt.

The invention will now be explained in more detail using schematic illustrations:

• In the 1 a sectional view of a transmission according to the invention is shown.
• In the 2 a multi-part planetary wheel of the transmission is shown in an oblique view.

As shown in the figures, the transmission has two planetary gear stages.

A bearing flange 17 is connected to the housing part 10 of the transmission, in which bearings are accommodated which support the input shaft 14 in a rotatable manner.

The input shaft 14 has a hollow shaft section in which internal splines are incorporated, which mesh with an external spline of a first sun gear shaft 15 of a first planetary gear stage that is inserted into the hollow shaft section.

The external spline is arranged on a first axial end area of the first sun gear shaft 15 .

This sun gear shaft 15 is rotatably mounted by means of a bearing 18 at its other axial end region, in particular that which faces away from the input shaft 14 .

The bearing 18 is accommodated in a second sun gear shaft 3, the second sun gear shaft 3 belonging to a second planetary gear stage.

With the first sun gear shaft 15 a toothing of an epicyclic gear is engaged, which is composed of a gear 8 and a planetary gear 11 .

The toothing of the planet gear 11 meshes with the toothing of the first sun gear shaft 15 .

Gear wheel 8 designed as an insert pinion is inserted into a recess in planet wheel 11 and connected to planet wheel 11 in a form-fitting manner by means of a feather key 9 . For this purpose, the hollow planet wheel 11 is attached to a cylindrical extension of the gear wheel 8, a keyway being incorporated in the cylindrical extension, into which the keyway 9 is inserted, which also protrudes into an axial groove of the planet wheel 11 .

An internally toothed ring gear is connected to the housing part 10 or constructed in one piece, in particular in one piece.

The toothing of the gear wheel 8 meshes with the internal toothing of the ring gear, the toothing of the planet wheel 11 meshes with the toothing of the first sun wheel shaft 15 .

The toothing of gear wheel 8, which is preferably designed as an involute toothing, has a smaller outside diameter, in particular the addendum circle diameter, than the toothing of planet wheel 11, which is preferably designed as involute toothing.

The inner diameter of the ring gear is smaller than the addendum circle diameter of the toothing of the planetary gear 11. The inner toothing of the ring gear is thus arranged at a radial distance from the toothing of the planetary gear 11, in particular at a smaller radial distance from the axis of rotation of the first sun gear shaft 15.

The gear wheel 8 is hollow and slipped onto a planet pin 13, which is mounted axially on both sides in the first planet carrier 6 via bearings (7, 12), in particular roller bearings. The bearings 7 and 12 are arranged axially outside the teeth of the gear wheel 8 and the planet wheel 11 .

The first planet carrier 6 is supported on the one hand by a bearing 16 accommodated in the bearing flange 17 and on the other hand by a bearing 19 which is accommodated in the housing part 10 .

The second sun gear shaft 3 has on its axial end area associated with the first sun gear shaft 15 external teeth, in particular splines, with which the second sun gear shaft 3 is inserted into an internally toothed axial end area of the first planetary carrier 6 .

The second sun gear shaft 3 has no direct bearing.

At its first end, the second sun gear shaft 3 is inserted into the first planetary carrier 6 and is thus mounted indirectly via the bearing 19 of the first planetary carrier 6 .

At its second axial end region, the second sun gear shaft 3 has a toothing that acts as a sun gearing, which meshes with, in particular three, second planetary gears 24, each of the second planetary gears 24 being rotatably mounted on a respective planetary pin 23 via bearings, in particular needle bearings .

The planet bolts 23 are accommodated in a double-sided planetary carrier 25 .

The teeth of the planet gears 24 are also in engagement with a second ring gear 1. For this purpose, the second ring gear 1 has internal teeth which are in mesh with the teeth of the planet gears 24. In addition, the internal toothing of the second ring gear 1 is axially extended, i.e. protrudes axially beyond the planetary gears 24, so that an externally toothed area of a support ring 2 can be inserted into the second ring gear 1 and this externally toothed area thus meshes with the internal toothing of the second ring gear 1 is bringable. In this way, the second ring gear 1 can be positively connected to the support ring 2 in the circumferential direction, i.e. in particular can be connected in a rotationally fixed manner,
In order to align the support ring 2 with the ring gear 1, the support ring 2 is slipped onto ring-shaped elevations which have finely machined alignment surfaces 21 and 22 on their radial outside. These ring-shaped elevations are formed on a cylindrical area of the housing part 10 which in the axial direction covers an area which is encompassed by the area covered by the second sun gear shaft 3 in the axial direction.

In particular, the support ring 2 is arranged on the side of the second planet gears 24 facing the first sun gear shaft 15 .

An inner ring of a bearing 20 is slipped onto the support ring 2, the outer ring of which is accommodated in a sleeve 27, in particular a bearing bush, which is non-rotatably connected to the planetary carrier 25, in particular by means of screws.

The outer ring of a second bearing 20 is also accommodated in the sleeve 27, the inner ring of which is slipped onto a cylindrically shaped area, in particular the bearing receiving area, of the housing part d10.

The sleeve 27 is arranged axially between the second planet gear 24 and the first sun gear shaft 15 .

In this way, the second planet carrier 25 is rotatably mounted via the sleeve 27 in that the sleeve 27 is mounted on the housing part 10 on the one hand via a bearing 20 and on the other hand via another bearing 20 together with the support ring 2 on the housing part 10 .

The area covered in the axial direction by the sleeve 27 overlaps with that of the two th planet gears 24 covered in the axial direction and is covered by the area covered by the second sun gear shaft 3 in the axial direction.

A seal accommodated in the sleeve 27 comprises a shaft sealing ring 4 whose sealing lip 4 runs on a finely machined surface of the housing part 10 and thus seals the sleeve 27 towards the housing part 10 . The sealing lip thus touches the housing part 10. The sleeve 27 has a seat for the shaft sealing ring 4.

The finely machined surface of the housing part 10 is arranged radially inside the sealing ring 3 and/or the sleeve 27 .

A dust seal 5 , preferably designed as a V-ring, seals the housing part 10 from the sleeve 27 .

The sleeve 27 has a radially continuous bore which is closed with a sealing plug 28 . When the sealing plug is removed and the transmission is switched off, oil can thus be refilled, in particular through the sleeve 27 . However, during operation of the transmission, the sleeve 27 is a rotating part and the oil refilling is therefore not executable.

The bore that runs radially through the sleeve 27, in particular a radial bore, opens out between the two bearings 20, so that their rolling bodies can be supplied with lubricant.

An axially directed bore, into which the radial bore opens or which crosses the radial bore, opens into a gap region, in particular an annular gap, arranged radially between sleeve 27 and the second ring gear.

Further recesses running through the support ring 2 enable the lubrication of the needle bearings of the second planet 24 and the teeth of the second planet 24.

The sleeve 27 acts as an axial extension of the second planet carrier 25 and surrounds the second ring gear 1 radially.

The gear wheel 8 is positively connected to the planet wheel 11 by means of the feather key 9, but the gear wheel 8 designed as a plug-in pinion is also inserted with its cylindrical extension into the planet wheel 11, this planet wheel being thermally shrunk on. During manufacture, the gear wheel 8 is heated before it is inserted, so that there is a temperature difference of more than 40° C. between the gear wheel 8 and the planet wheel 11 .

In this way, the connection between the gear wheel 8 and the planet wheel 11 is not only designed in a form-fitting manner, but also in a force-fitting manner.

In further exemplary embodiments according to the invention, the sleeve 27 is designed in one piece with the second planetary carrier 25, in particular in one piece.

Reference List

1

ring gear

2

support ring

3

second sun gear shaft

4

shaft seal

5

Dust seal, especially V-ring

6

first planet carrier

7

camp

8th

gear

9

Adjusting spring

10

housing part

11

planet wheel

12

camp

13

first planet bolt

14

input wave

15

first sun gear shaft

16

camp

17

bearing flange

18

camp

19

camp

20

camp

21

alignment surface

22

alignment surface

23

planet bolt

24

planet

25

planet carrier

26

shaft nut

27

Sleeve, in particular bearing bush

28

sealing plug

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

• US1968604A [0003]
• CN 106274459A [0004]
• CN 103791033A [0005]
• US 1985964 A [0006]
• DE 102019006068 A1 [0007]
• DE 19922651 A1 [0008]
• DE 102014213669 A1 [0010]
• DE 1430245 A [0011]
• DE 102007034449 A1 [0012]

Claims (15)

Transmission with a first planetary gear stage, which has a first sun gear shaft, internal teeth, in particular a first ring gear connected to a housing part or a first ring gear designed in one piece with the housing part, and an epicyclic gear, characterized in that the epicyclic gear has a planet gear, in which the cylindrical extension, in particular a pin, of a gear designed as a plug-in pinion is inserted, with the toothing of the planetary gear meshing with a toothing of the first sun gear shaft, with the toothing of the gearwheel meshing with a toothing of the internal toothing, - with the planetary gear being connected by means of a keyway to is non-rotatably connected to the gear wheel, - and/or wherein the extension has a groove, in particular a feather keyway, in which a feather key is accommodated, which also at least partially protrudes into a groove of the gear wheel, in particular for the circumferential direction around the axis of rotation d es planetary gear positive connection of the planet gear with the gear. gear after claim 1 , characterized in that the first planet wheel is thermally shrunk onto the extension and / or is thermally joined, in particular so that the gear is non-positively connected to the first planet wheel. Transmission according to one of the preceding claims, characterized in that the revolving wheel is slipped onto a planet bolt, the planet bolt being rotatably mounted axially on both sides via a respective bearing accommodated in a planet carrier of the transmission, in particular the bearings being spaced apart from the gearwheel in the axial direction and/or from the planet wheel. Transmission according to one of the preceding claims, characterized in that an input shaft of the transmission is rotatably mounted by means of bearings accommodated in a bearing flange of the transmission, the bearing flange being connected to one or the housing part of the transmission, in particular by means of screws, the first sun gear shaft having a Gearing, in particular splined gearing, which is inserted into a hollow area of the input shaft, in particular hollow shaft section, for the non-rotatable connection of the input shaft to the sun gear. Transmission according to one of the preceding claims, characterized in that the first sun gear shaft is rotatably mounted at its end region facing away from the input shaft by means of a bearing which is accommodated in a second sun gear shaft, in particular the inner ring of the bearing being slipped onto the first sun gear shaft and the The outer ring of the bearing is accommodated in the second sun gear shaft. Transmission according to one of the preceding claims, characterized in that the first planetary carrier has internal teeth into which an externally toothed area of the second sun gear shaft is inserted and with which the externally toothed area of the second sun gear shaft is engaged, in particular for the non-rotatable connection of the first planetary carrier to the second Sun gear shaft, in particular wherein the first planet carrier is rotatably mounted via a bearing accommodated in the housing part. Transmission according to one of the preceding claims, characterized in that on the end region of the second sun wheel shaft facing away from the input shaft in the axial direction, the second sun wheel shaft has teeth which mesh with the teeth of a second planet wheel which is mounted on a second planet bolt, in particular by means of Needle bearings is rotatably mounted, wherein the second planet pin is received in a planet carrier, wherein the toothing of the second planetary gear is in engagement with the internal toothing of a second ring gear. Transmission according to one of the preceding claims, characterized in that the second ring gear is non-rotatably connected to a support ring, in particular in that the support ring is at least partially inserted into the ring gear, the support ring having external teeth which mesh with the internal teeth of the ring gear. Transmission according to one of the preceding claims, characterized in that on the housing part, in particular based on the Axis of rotation of the second sun gear shaft, radially directed, annular elevations, in particular elevations, are formed, which have alignment surfaces running around in the circumferential direction, onto which the support ring is pushed, in particular for aligning the support ring together with the second ring gear, in particular the alignment surfaces being separated from one another in the axial direction are spaced. Transmission according to one of the preceding claims, characterized in that the first sun gear shaft is aligned coaxially with the second sun gear shaft. Transmission according to one of the preceding claims, characterized in that the second planet carrier is connected to a sleeve which radially surrounds the second ring gear, in particular a gap region being formed between the second ring gear and the sleeve. Transmission according to one of the preceding claims, characterized in that a first bearing is placed with its inner ring on a cylindrical section of the housing part and its outer ring is received in the sleeve and / or that a second bearing, in particular an outer ring of a second bearing, in the Sleeve is received, the inner ring is fitted onto the support ring, in particular wherein the support ring has a step against which the second bearing is employed. Transmission according to one of the preceding claims, characterized in that the support ring is delimited in the axial direction by a shaft nut screwed onto a screw thread applied to the housing part. Transmission according to one of the preceding claims, characterized in that a shaft sealing ring received by the sleeve seals towards the housing part, in particular a sealing lip of the shaft sealing ring bears against a finely machined surface of the housing part, in particular a dust seal, in particular a dust seal designed as a V-ring , the sleeve seals in addition to the housing part. Transmission according to one of the preceding claims, characterized in that a radial bore passing through the sleeve opens into a spatial area adjoining the first and second bearings, in particular with an axial bore introduced into the sleeve crossing the radial bore and opening into a spatial area in which the toothing of the second planet gear is located.

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