DE102011006285A1 - Planetary carrier i.e. ravigneaux gearset part, for use in e.g. planetary gears utilized in powertrain of vehicle to separate drive torques, has support portions occupying certain degrees of circular arc portion - Google Patents

Abstract

The carrier (1) has multiple planetary bolts (4a, 4b) extended between two side plates (2a, 2b). The side plates are supported against each other in an axial direction in support portions (7) over seams (6a, 6b) such that receiving areas for planetary gears (5a, 5b) are formed between the support portions in rotation direction. The bolts with the gears are arranged in the areas. The support portions has small pitch circle diameter, where the support portions on a pitch circle of the bolts occupy less than 50 degrees of a circular arc portion.

Description

The invention relates to a planetary carrier having a first side window, with a second side window and with a plurality of planet pins, which are arranged between the first and the second side plate and with a plurality of planetary gears, which are rotatably mounted on the planet shaft, wherein in at least one Side window beads are formed, over which the side windows are supported in the axial direction against each other in support areas, so that receiving areas for the planetary gears are formed in the direction of rotation between the support areas, wherein two planet pins are arranged with planetary gears in each receiving area. The invention also relates to a planetary gear with the planet carriers.

Planetary gear are u. a. used in the powertrain of vehicles to divide or merge drive torques. For example, planetary gear can be designed as longitudinal differentials or as axle differentials. Planetary gears are particularly space-saving if they are designed as so-called spur gear differentials, that is to say have toothed gears on the front side.

Such a spur gear is for example from the document DE 10 2009 032 286 A1 known, which is probably the closest prior art. The disclosed in the publication spur gear has on both sides a side cover, which alternately has a mounting area and a receiving area for planetary gears in the direction of rotation. In the attachment area, two rivets each are arranged offset in the direction of rotation and couple the lids to one another and to a planetary carrier with a spur gear tooth. The receiving regions have flanks extending in the radial direction, the flanks of a receiving region being arranged almost parallel to one another. The attachment regions likewise have flanks, wherein the flanks of a fastening region form an obtuse angle in an axial plan view.

Field of the invention

The invention has for its object to propose a planet carrier, which is easy to assemble. This object is achieved by a planet carrier with the features of claim 1 and by a planetary gear with the features of claim 9. Preferred or advantageous embodiments of the invention will become apparent from the dependent claims, the following description and the accompanying drawings.

The invention thus relates to a planetary carrier for a planetary gear, wherein the planetary gear suitable for use in a drive train in a vehicle and / or is formed. The planet carrier and / or the planetary gear is designed as a spur gear, so in particular the planet gears and optional complementary the sun gears and / or ring gears frontally and / or circumferentially, radially outward, geared. This embodiment allows in the axial direction to a central axis of the planet carrier a very space-saving arrangement of the components.

The planet carrier comprises a first and a second side window, wherein between the two side windows a plurality of planet pins are arranged, on which a plurality of planetary gears are rotatably mounted. Particularly preferably exactly one planetary gear is rotatably mounted on each planetary pin. The planet pins are particularly preferably fixed in the first and the second side window.

Beading is formed in at least one of the side windows, preferably in both side windows, that is to say regions which protrude in the axial direction in relation to adjacent areas over which the side windows are supported against one another in the axial direction, possibly with the interposition of further components. Looking at the planet carrier in an axial plan view, so support areas and receiving areas for the planetary gears are alternately formed in the direction of rotation. In each of the receiving areas at least or exactly two planet pins are arranged with planetary gears, wherein the planet pins are arranged offset in the radial direction to the central axis of the planet carrier and / or in the direction of rotation about the central axis of each other. In particular, the at least two planetary gears have different axes of rotation per receiving area.

Particularly preferably, the planetary pin or the planet gears can be assigned to a first and a second planetary gear set, wherein in some embodiments, the diameters of the pitch circles of the planetary gear sets may differ. For purposes of definition, the pitch circle of a planetary gearset is considered to be a circle having a center on the central axis and a diameter passing through the centers of the axes of rotation of the planetary gears or planetary pins associated with the planetary gearset.

According to the invention, it is proposed that each of the support areas on the pitch circle of the planet pins with the smallest pitch circle diameter occupy a circular arc section of less than 50 degrees. Thus, the support area at a circle around the central axis of the planet carrier with a diameter that the smaller of the Partial diameter of the planetary gear sets corresponds to a very small angular range, in order to secure sufficient space for the planet gears in the circumferential direction. In the event that the pitch circle diameters of the planetary gear sets are the same, the common pitch circle is used as the reference pitch circle and forms the smallest pitch circle diameter. By this measure, the space for the planetary gears is increased so that they can be sized larger and on the other hand easier to be mounted.

The boundary between the receiving area and the supporting area is preferably determined as follows: The side window defines a plane, wherein the boundary between receiving area and supporting area is arranged in the plane where the receiving area decreases in the axial direction. Thus, a transition radius between the receiving area and the support area is already assigned to the support area, since the determining factor for the limit of the installation space in the direction of rotation for the planetary gears.

In a preferred development of the invention, each support region occupies a circular sector of less than 50 degrees. The boundaries of the support region in this embodiment extend within a "cake piece" having an opening angle of less than 50 degrees. With this further restriction, it is achieved that even in radial regions larger or smaller than the smallest pitch circle, sufficient space remains for the planetary gears or for access from radially outside to the planetary gears.

In a simple design refinement, it can be provided that precisely one passage opening for a connecting element is arranged in the support region. The passage opening may be formed, for example, as a circular opening, through which a bolt or a rivet is inserted in the assembled state, to fix the two side windows against each other or to connect with each other.

It is structurally preferred that the support areas have side flanks which, relative to a support area, together form an angle which is equal to or smaller than the angle of the circular arc section on the smallest circle of the planet pins. While in the prior art, the support areas rather have an obtuse angle, it is preferred in the advantageous embodiment of the invention that the side edge include an acute angle, preferably an angle which is smaller than the angle of the circular arc portion of 50 °. Viewed in an axial plan view, this means that the side edges define a circular sector, in the area of which the piercing point of the central axis of the planet carrier is arranged, but the center of the circular sector is farther away than said piercing point.

It is particularly preferred if the support region is designed to be open to the outside in the radial direction or preferably to be straight. This embodiment supports easy accessibility of the planet gears from radially outside.

In a preferred embodiment of the invention, at least one side window has a hub portion, which forms part of a form-locking connection, wherein the positive connection is formed as a polygonal connection. The positive connection allows a shaft-hub connection, wherein the hub portion has a receiving area for the shaft, wherein the receiving area in a cross section perpendicular to the central axis has a polygonal shape.

The advantages of polygon joints are in particular that they are self-centering, have a low tendency to notch effect, have good dynamic properties and can absorb very high torques. Furthermore, the form-locking connection is designed as a detachable connection, so that the mounting of the planet carrier is made possible or facilitated.

The basic shape of the polygon shape is preferably formed as a regular polygon, in particular as a triangle or as a quadrilateral or square. In modified embodiments, however, can also be used with 5, 6, 7, 8 or more corner areas. Particularly preferred is the polygon shape and / or the polygon connection according to the DIN 32711 formed and realized in particular as a there defined T3G triangle or P4C quadrilateral. Particularly preferably hub portion is formed in one piece or as a forming area on the side window.

In the production, it is advantageous if the side window (s) is or are produced as a formed part. In particular, the manufacture of the side window via a cold forming. For example, in a first manufacturing step, a sheet metal blank, z. B. a blank made from a sheet and formed in a second manufacturing step, the beads or the hub portion. This type of production allows low production costs per component, especially for a large number of items.

Another object of the invention relates to a planetary gear with the planet carrier according to one of the preceding claims or as previously described.

Particularly preferably, the planet carrier is designed as part of a Ravigneaux set.

In the Ravigneaux theorem, it is provided that planet gears of a first planetary gear mesh with a sun gear, planet gears of a second planetary gear set mesh with a ring gear, and planet gears of the first and second planetary gear mesh with each other. In particular, a planetary gear of a first planetary gearset and a planetary gear of the second planetary gearset are arranged in each receiving area, which mesh with each other. Particularly preferably, the planetary gear set whose planetary gears mesh with the sun gear defines the smallest pitch circle diameter of the planet pins.

Further features, advantages and effects of the invention will become apparent from the following description of a preferred embodiment of the invention and the accompanying figures. Showing:

1 a schematic three-dimensional representation of a planet carrier as a first embodiment of the invention;

2 the planet carrier in the 1 in a schematic plan view from the axial direction.

The 1 shows in a schematic three-dimensional representation of a planet carrier 1 as a first embodiment of the invention. The planet carrier 1 is part of a planetary gear, not shown, and is formed in this particular embodiment as a planet carrier Ravigneaux a sentence. The Ravigneaux set is used for example in automatic transmissions in vehicles.

The planet carrier 1 includes two side windows 2a , b, in their surface extension in the coarse form parallel to each other and perpendicular to a central axis 3 of the planet carrier 1 extend. Between the side windows 2a , B are planetary bolts 4a , b of two different planetary gear sets. The planet bolts 4a , b are each with their one free end in the side window 2a and with the second free end in the side window 2 B established. On the planet stud 4a , b are planet gears 5a , B rotatably mounted, which in turn are assigned to the two planetary gear sets.

Functionally, a (not-shown) sun gear meshes with the planetary gears 5a of the first planetary set, which in turn with the planetary gears 5b of the second planetary gear meshes. The planet wheels 5b of the second planetary gear set mesh with a ring gear (not shown).

In the circumferential direction regularly spaced beads 6a , b in the side windows 2a , b formed, which the side windows 2a respectively. 2 B in the axial direction to the central axis 3 support each other. In each case a pair of beads 6a , b forms a support area 7 , Between the side windows 2a , b can in the support areas 7 Optionally, further components may be arranged as shown in the 1 through the graphic space between the beads 6a , b, is indicated. In alternative embodiments, the side windows 2a , b in the support area 7 be arranged contacting. In every support area 7 is in the side windows 2a , B each exactly one through hole 8th arranged so that the two side windows in each support area 7 2a , b can be connected by a bolt-nut or rivet joint.

At the side window 2a is in the middle a hub section 9 in the opposite direction to the beads 6a formed, which in a cross section perpendicular to the central axis 3 a polygonal opening area 10 having. The opening area 10 acts with a polygonal in the outer periphery and complementarily shaped shaft (not shown) together, so that they together form a positive and non-rotatable shaft-hub connection. The inner contour of the opening area 10 corresponds to z. B. a P3G triangle, as shown in the DIN 32711 is fixed.

Both side windows 2a , b including the beads 6a , B and the hub portion 9 are each formed as a forming part. In particular, these are manufactured by means of drawing technology, in particular by means of cold forming.

The 2 shows a schematic plan view of the side window 2a , where auxiliary lines are drawn in to simplify the description: The axes of rotation of the planet pins 4a of the first planetary gear set define a first pitch circle 11a , the axes of rotation of the planet pins 4b define a second pitch circle 11b which has a larger diameter. The transition between reception areas 12 and the support areas 7 will - as it turns out 1 results - by one end of the in the receiving area 12 formed recording room 13 Are defined. Once in the recording room 13 the space for the planet gears 5a , b is reduced, the recording room applies 13 as finished. Through this definition of the transition from shooting range 12 in the support area 7 be two flanks 14 of the support area 7 defined, which is radial to the central axis 3 extend.

The intersection between the flanks 14 and the first circle 11a defines a circular arc section 15 which has an angular range of less than 50 degrees of the entire arc of the circle 11a covers. In the illustrated embodiment, the circular arc section 15 only an angle range of 40 degrees. From the 2 also shows that the entire support area 7 to the flanks 14 is covered by a circular sector, which is also covered in the angular range of less than 50 degrees or 40 degrees. After three support areas 7 are regularly distributed in the direction of circulation, results for the receiving areas 12 a total available angular range of 210 degrees and 240 degrees, respectively. Due to the slim design of the support areas 7 in the direction of rotation thus remains a wide space for receiving the planetary gears 5a , b.

The polygon shape of the opening area is triangular in its basic form, the three corner areas 16a , b, c in the direction of rotation about the central axis 3 are regularly spaced from each other. Between the corners 16a , b, c extend side surfaces 17a , b, c, which are formed in the mentioned cross-section as sections of circular lines, wherein the circular lines each have the same radius.

LIST OF REFERENCE NUMBERS

1

planet carrier

2a, b

side windows

3

central axis

4a, b

planet shaft

5a, b

planetary gears

6a, b

beading

7

support area

8th

Through opening

9

hub portion

10

opening area

11a, b

pitch circle

12

reception area

13

accommodation space

14

flanks

15

Arc section

16a, b, c

corner areas

17a, b, c

faces

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 102009032286 A1 [0003]

Cited non-patent literature

• DIN 32711 [0017]
• DIN 32711 [0029]

Claims (10)

Planet carrier ( 1 ) with a first side window ( 2a ), with a second side window ( 2 B ), with a plurality of planet pins ( 4a , b) extending between the first and second side windows ( 2a , b) and with a plurality of planet gears ( 5a , b), which on the planet pins ( 4a , b) are rotatably mounted, wherein in at least one side window ( 2a , b) beading ( 6a , b) are formed over which the side windows ( 2a , b) in the axial direction against each other in support areas ( 7 ), so that in the direction of rotation between the support areas ( 7 ) Recording areas ( 12 ) for the planetary gears ( 5a , b) are formed, wherein in each receiving area ( 12 ) at least two planet pins ( 4a , b) with planet wheels ( 5a , b), characterized in that each support region ( 7 ) on the pitch circle ( 11a ) of the planet pins ( 4a ) with the smallest pitch circle diameter a circular arc section ( 15 ) of less than 50 degrees. Planet carrier ( 1 ) according to claim 1, characterized in that each support area ( 7 ) occupies a circular sector of less than 50 degrees. Planet carrier ( 1 ) according to one of the preceding claims, characterized in that in the support area ( 7 ) exactly one through hole ( 8th ) is arranged for a connecting element. Planet carrier ( 1 ) according to one of the preceding claims, characterized in that the support areas ( 7 ) Side flanks ( 14 ), which together form an angle which is equal to or smaller than the angle of the circular arc section (FIG. 15 ) on the smallest circle ( 11a ) of the planet pins ( 4a ). Planet carrier ( 1 ) according to one of the preceding claims, characterized in that at least one side window ( 2a , b) a hub section ( 9 ), which forms part of a positive connection, wherein the positive connection is formed as a polygonal connection. Planet carrier ( 1 ) according to one of the preceding claims, characterized in that the polygon connection is based on a regular polygon as the basic form. Planet carrier ( 1 ) according to one of the preceding claims 5 or 6, characterized in that the polygon shape according to DIN 32711 is formed and / or that the polygonal shape as a triangle, in particular as a P3G triangle, or as a quadrilateral, in particular as a P4C quadrangle is trained. Planet carrier ( 1 ) according to one of the preceding claims, characterized in that the side window ( 2a , b) is formed as a forming part. Planetary gear with the planet carrier ( 1 ) according to any one of the preceding claims. Planetary gear according to claim 9, characterized in that the planet carrier forms part of a Ravignauxsatzes.

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