DE102006060298A1 - Planetary toothed gear for stepped planetary gears, has smaller gear teeth part in planetary gears, which is engaged with internal geared wheel - Google Patents

Abstract

The planetary toothed gear (1) comprises a sun gear (2), internal geared wheel (7), a planet carrier with multiple stepped planetary gears (3,4,5,6). The planetary gears have small and large gear teeth parts (8,9).The smaller gear teeth part of the planetary gears stays engaged with the internal geared wheel and the larger gear teeth part engages with the sun gear. The number of teeth of small gear teeth part that engages with the internal geared wheel is a prime number. An independent claim is also included for a method of mounting stepped planetary gears.

Description

The The present invention relates to a multi-stage planetary gear transmission with undivided stepped planets according to the preamble of the claim 1. Furthermore, the invention relates to a method for Assembly of the stepped planetary of a multi-stage planetary gear according to the invention.

multistage Planetary gear with stepped planetary to increase the ratio across from simple planetary gear sets are known from the prior art. They usually have one as the output serving planet carrier with several planet wheels, in mesh with a ring gear. Here, the ring gear is usually for example about a mounting flange, held stationary or rotationally fixed with a Housing connected; the concentrically arranged to the transmission main axis of the planetary gear Input shaft is directly or indirectly with a motor (eg electric motor) connected and has a drive pinion. It is intended that in the planet carrier stored planet gears each as a stepped wheel, each with a pinion for engagement in the ring gear and a bigger bike are designed for engagement in the drive pinion.

transmission of the type mentioned in the beginning, however, are little used in practice, because the tooth positions of all stepped planetary gears of a transmission to the common Sun gear during assembly must match sufficiently accurately. Around to achieve this, it has been proposed to use step wheels, their partial toothing during assembly, for example via flange connections or other clamping mechanisms set limited rotatable can be. Such split stage planets are disadvantageously very expensive to manufacture and need sometimes relatively much space.

at Use undivided planetary gears are previously exactly matching Tooth positions of the partial toothings of the stepped planets during the Production to produce what is usually with reference to a reference tooth to be marked or takes place on a reference gap to be identified.

These Procedure results in high costs and also leads to undesirable or inevitable position errors, so that the power distribution is worsened on all stage planets. This is at planetary gears anyway by pitch error of the planet carrier, tolerances of the gears and planetary bearings adversely affected. Position error in undivided Stepped planets are allowed therefore be very small, and much smaller than the deviations, the usual production methods would result in rational mass production. At the same time are complicated Mounting conditions already in the design, in the choice of the number of teeth and later then also during the assembly process to observe and largely avoid.

From the EP 1040284 B1 Applicant's claim is a planetary gear having a sun gear disposed on a central shaft, with at least one ring gear and a planetary carrier, comprising a group of stepplanes with large and small step wheels mounted therein, the large step gears of which mesh with the sun gear. Here, the sun gear is flying radially mounted in the meshing with the large step wheels.

In the planetary gear according to EP 1040284 B1 It is envisaged that the number of teeth of the large step wheels is not integer divisible by the number of teeth of the small step wheels to achieve a radial adjustability of the sun gear alone through different rotational positions during assembly of the stepped planet. The transmission according to EP 1040284 B1 Preferably, it has two groups of tiered planets, each providing a paired power split, with only one branch on two power paths due to the mountability and the paired arrangement per tierplanet.

Of the present invention is based on the object, a multi-stage To specify planetary gear units with undivided stepped planets, which is easy to install and a sufficiently good power distribution on all stage planets. Furthermore, a method for mounting the stepped planetary planetary gear according to the invention be specified.

These Task is for a multi-stage planetary gear by the features of Patent claim 1 solved. A method for assembling the stepped planets of the multi-stage according to the invention Planetenzahnradgetriebes is the subject of claim 3. Other Embodiments of the invention and advantages will be apparent from the corresponding subclaims.

Accordingly, a multi-stage Planetenenzahnradgetriebe is proposed with undivided stepped planetary, comprising a sun gear, at least one ring gear, a planet carrier several Stufenplaneten, each having a small pitch and a large pitch, the small pitch of the stepped planet with the ring gear is engaged and the large part of teeth the stepped planet is in engagement with the sun gear, in which the numbers of teeth of the two partial teeth the stepped planets are chosen so that they have no common divider, wherein the larger number of teeth is not integer divisible by the smaller number of teeth. Furthermore, the number of teeth of meshing with the ring gear, smaller diameter partial teeth of the stepped planetary is a prime, for example, 13, 17, 19, 23, etc.

hereby arise for a stepped planet whose smaller sub-teeth have N teeth, N different installation options, each one another position assignment of the two partial teeth of the stepped planet (the pinion becomes one Number of teeth twisted reinstalled).

through one below described method, with respect to a particular stepped planet, for every the possible Installation positions or installation options the respective change the tooth gap position be calculated to the corresponding tooth of the drive pinion, so that the number n of teeth and the twist direction for the corrected installation of the smaller partial toothing can be determined.

According to the invention, all stage planets are initially mounted in any position, with a stepped planet serves as a reference base and its installation position, which has no position error, is not changed. Subsequently, the tooth position errors of the large splines of the other stepped planets are measured as travel on the pitch circle of the major spline of the respective step planet and including the direction of deviation (clockwise or counterclockwise) as data for calculating the number of teeth around which the small one gearing 8th to be rotated as well as the direction of rotation used for the corrected installation of the small partial toothing. Accordingly, in the case of four stepped planets, a first tiered planet is left unchanged as the reference base, and the other three are adjusted one after the other in the Umsteckverfahren.

at The Umsteckjustierung arise depending on the choice of transmission parameters inevitable Residual errors, measured by the large gearing of the stepped planet in the order of magnitude of 50 μm Degen. This means that the errors related to the small spline the tiered planets for the engagement in the ring gear and for the planetary storage is relevant on the order of 10 microns. Given the pitch errors on the planet carrier, which are in about 25 microns and detected by the method presented here (Umsteckjustierung) and balanced, results in a good distribution of benefits on all stage planets.

In Advantageously, the inventive method can at least partially automated become; for example the tooth gap positions be scanned automatically, with the captured values in a Calculation program are entered, which the calculated values for the Twist angle outputs.

The The invention will be explained in more detail below with reference to the accompanying figures by way of example.

It demonstrate:

1 a schematic diagram of the wheel assembly of an embodiment of a planetary gear according to the invention comprising four stepped planets before the Umsteckjustierung;

2 a detailed view of the arrangement of the wheels 1 ;

3 a schematic diagram of the wheel assembly of the embodiment 1 after the Umsteckjustierung and

4 a detailed view of the arrangement of the wheels 3 ,

In 1 is the wheel assembly of an embodiment of a planetary gear according to the invention 1 with undivided stepped planets 3 . 4 . 5 . 6 shown. The planetary gear transmission 1 includes a sun wheel 2 , a ring gear 7 , a planet carrier with four stepped planets 3 . 4 . 5 . 6 , each Weil's a small Teilverzahnung 8th and a large partial toothing 9 have, wherein the small partial toothing 8th the stepped planet 3 . 4 . 5 . 6 with the ring gear 7 engaged and the large partial teeth 9 the stepped planet 3 . 4 . 5 . 6 with the sun wheel 2 engaged. According to the invention, the numbers of teeth of the two partial teeth of the stepped planets are chosen so that they have no common divisor (except 1 ), wherein the larger number of teeth is not integer divisible by the smaller number of teeth and wherein the number of teeth with the ring gear 7 combing small Teilverzahnungen 8th the stepped planet 3 . 4 . 5 . 6 is a prime, in this example 17.

At the in 1 The arrangement shown are the stepped planets 3 . 4 . 5 . 6 mounted in any position, so that as already explained, the position errors in the tooth positions of the large splines of the stepped planetary 4 . 5 . 6 are big, as based on 2 illustrated. The step planet 3 serves as a reference; its installation position, which has no position error, will not be changed.

According to the invention for assembly the stepped planets the tooth position errors of the large splines of the other stepped planets 4 . 5 . 6 measured as a distance on the pitch circle of the large partial toothing of the respective stepped planet, wherein from this measurement the angle of rotation, which corresponds to a number of teeth of the small partial toothing, and the direction of rotation for the corrected installation of the small partial toothing are determined. Based on these values, the tiered planets become 4 . 5 . 6 one after the other adjusted in the Umsteckverfahren.

In 3 is a wheel assembly of the embodiment of 1 shown after the Umsteckjustierung, wherein 4 a detailed view of the arrangement of the wheels according to 3 represents. How out 3 and 4 ersicht Lich, the implementation of the method according to the invention in a simple way to a minimization of position errors and results in a good power distribution to all with the sun 2 combing step planets 3 . 4 . 5 . 6 ,

1

Planetary gear transmission

2

sun

3

step planet

4

stepped planet

5

step planet

6

step planet

7

ring gear

8th

small part teeth

9

large partial toothing

Claims (4)

Planetary gear transmission ( 1 ) with undivided stepped planets ( 3 . 4 . 5 . 6 ) comprising a sun gear ( 2 ), at least one ring gear ( 7 ), a planet carrier with several stepped planets ( 3 . 4 . 5 . 6 ), each having a small partial toothing ( 8th ) and a large partial toothing ( 9 ), wherein the small partial toothing ( 8th ) of the stepped planets ( 3 . 4 . 5 . 6 ) with the ring gear ( 7 ) is engaged and the large partial toothing ( 9 ) of the stepped planets ( 3 . 4 . 5 . 6 ) with the sun wheel ( 2 ), wherein the numbers of teeth of the two partial toothings ( 8th . 9 ) of the stepped planets ( 3 . 4 . 5 . 6 ) are chosen so that they have no common divider and wherein the larger number of teeth is not integer divisible by the smaller number of teeth, characterized in that the number of teeth of the ring gear ( 7 ) meshing small partial teeth of the stepped planets ( 3 . 4 . 5 . 6 ) is a prime number. Planetary gear transmission ( 1 ) with undivided stepped planets ( 3 . 4 . 5 . 6 ), according to claim 1, characterized in that it comprises four stepped planets ( 3 . 4 . 5 . 6 ) having. Method for assembling the stepped planets ( 3 . 4 . 5 . 6 ) of a planetary gear transmission ( 1 ) with undivided step planets, in particular a planetary gear transmission according to claim 1 or 2, characterized in that all stage planets ( 3 . 4 . 5 . 6 ) are initially mounted in any position, with a stepped planet ( 3 ) is used as a reference base and its installation position, which has no position error, is not changed, and then the tooth position error of the large splines ( 9 ) of the other tiered planets ( 4 . 5 . 6 ) as a path on the pitch circle of the larger partial toothing ( 9 ) of the respective stepped planet ( 4 . 5 . 6 ) and including the direction of deviation (clockwise or counterclockwise) as data for calculating the number of teeth around which the small teeth ( 8th ) and the twisting direction for the corrected installation of the small partial toothing can be used, wherein the stepped planetary ( 4 . 5 . 6 ) based on the determined values for the number of teeth around which the small teeth ( 8th ) is to be rotated and adjusted for the direction of rotation successively in the Umsteckverfahren. Method for assembling the stepped planets ( 3 . 4 . 5 . 6 ) of a planetary gear transmission ( 1 ) with undivided stepped planets according to claim 3, characterized in that the tooth gap positions are automatically scanned, wherein the detected values are entered into a computer program which determines the values for the number of teeth around which the small teeth ( 8th ) of the respective stepped planet ( 4 . 5 . 6 ) is to be twisted and outputs for the twisting direction.