Planetary gear system

1 . A planetary gear system comprising:

a housing;

a sun gear;

a planet carrier;

at least one planet gear; and

a ring gear;

wherein the planet carrier is rotatably mounted in the housing;

wherein the housing defines an assembly direction for assembly of the planet carrier and the planet carrier has a bearing seat on its outer side which is arranged adjacent to an insertion end of the planet carrier and behind the ring gear in the assembly direction in the use position of the planet carrier and has an outer diameter which is smaller than an addendum circle diameter, of the ring gear;

wherein a bearing seat of the planet carrier, which is arranged in front of the ring gear and/or adjacent to an end of the planet carrier facing away from the insertion end in the assembly direction and in the use position of the planet carrier, has a diameter which is larger than the addendum circle diameter, of the ring gear and/or larger than a diameter of the bearing seat of the planet carrier adjacent to the insertion end, characterized in that the at least one planet gear is designed as a stepped planet gear, has two bearing seats and at least two toothings, namely a sun gear toothing meshing with the sun gear and a ring gear toothing meshing with the ring gear, in that the ring gear toothing of the planet gear is arranged between the two bearing seats of the planet gear, in that a bearing seat of the planet gear is arranged between an insertion end of the planet gear and the ring gear toothing;

wherein this bearing seat has an outer diameter which is smaller than the outer diameter of the ring gear toothing, in that the other bearing seat of the planet gear is arranged between the ring gear toothing and the sun gear toothing of the planet gear, in that the planet carrier has at least one planet holder for the at least one planet gear, and in that the planet holder has an insertion opening through which the at least one planet gear can be inserted into the planet holder in an assembly direction in its use position;

wherein the at least one planet holder has, adjacent to its insertion opening, a bearing seat for an outer ring, of a pivot bearing of the at least one planet gear, which has an inner diameter which is at least as large as the outer diameter of the ring gear toothing of the at least one planet gear, and

wherein the pivot bearing arranged on this bearing seat has an outer diameter which is at least as large as the outer diameter of the ring gear toothing of the at least one planet gear.

2 . A planetary gear system according to claim 1 , wherein the housing has the planet carrier holder with the insertion opening for the planet carrier, through which the assembly direction of the planet carrier is defined, and/or wherein the planet carrier is formed in one piece.

3 . A planetary gear system according to claim 1 , wherein the planet carrier has on its outer side in relation to its axis of rotation (R) two bearing seats ( 8 , 12 ) which are axially spaced apart from one another and between which the ring gear is arranged when the planet carrier is in the use position.

4 . A planetary gear system according to claim 1 , wherein the planet carrier has an output shaft, or is designed as an output shaft.

5 . A planetary gear system according to claim 1 , wherein the at least one planet gear is rotatably mounted in the planet carrier and meshes with the sun gear and with the ring gear.

6 . A planetary gear system according to claim 1 , wherein the assembly direction of the planet carrier into the housing and the assembly direction of the at least one planet gear into the planet holder coincide, and/or wherein the planet holder is designed as a blind hole or as a stepped bore.

7 . A planetary gear system according to claim 1 , wherein the planet carrier has at least one side opening into the planet holder of the planet carrier.

8 . A planetary gear system according to claim 1 , wherein the two toothings of the planet gear differ, and/or wherein the two toothings are axially spaced from each other with respect to an axis of rotation of the planet gear.

9 . A planetary gear system according to claim 1 , wherein the planet holder has a side opening aligned transversely to the axis of rotation (R) of the planet carrier for the ring gear toothing of the planet gear.

10 . A planetary gear system according to claim 1 , wherein a radial bearing, is arranged on the bearing seat, which is arranged between the insertion end of the planet gear and the ring gear toothing, the outer diameter of which is smaller than the outer diameter of the ring gear toothing of the at least one planet gear.

11 . A planetary gear system according to claim 10 , wherein the ring gear toothing of the at least one planet gear is a helical toothing and/or wherein the sun gear toothing of the at least one planet gear is a helical toothing.

12 . A planetary gear system according to claim 1 , wherein a helical toothing of the planetary gear system between the at least one planet gear and the sun gear and a helical toothing of the planetary gear system between the at least one planet gear and the ring gear of the planetary gear system are matched to each other in such a way that an amount of an effective axial force resulting from axial forces caused by the helical toothings during operation of the planetary gear is less than 10% of an amount of a smallest of the axial forces caused by the helical toothings in each case, or in that axial forces caused by the helical toothings during operation of the planetary gear cancel each other out.

13 . A planetary gear system according to claim 12 , wherein a ratio of the helix angles of the helical toothings corresponds to a ratio of the operating pitch diameters of the helical toothings.

14 . A planetary gear system according to claim 1 , wherein the at least one planet gear has a planetary shaft and the sun gear toothing is formed on a sun pinion which is arranged on the planetary shaft.

15 . A planetary gear system according to claim 1 , wherein the planetary gear system has at least one axial sliding washer, which is assigned to each pivot bearing of the planet gear.