Planetary gear carrier arrangement of a planetary gear set

Abstract

Planetary gear carrier arrangement (1) of a planetary gear in which a number of planet gears (2) are rotatably arranged on each bearing pin (3) about an axis of rotation (a), wherein the bearing of the planet gear (2) on the bearing pin (3) is effected by a radial bearing (4) and an axial bearing (5) and wherein the axial bearing (5) is effected by at least one bearing disk (5), wherein the bearing disc (5) has at least one axially extending projection (7) along its circumference at a radially internal recess (6), wherein the radial bearing (4) comprises at least one needle roller bearing (4), wherein the needle roller bearing (4) comprises a cage (8), wherein the cage (8) has a radially inward surface (9) which is designed for the attachment of at least one projection (7), characterized by that the radially inner surface (9) is a recess that is incorporated into the cage (8).

Description

Field of invention

[0001] The invention relates to a planetary gear carrier arrangement of a planetary gear unit in which a number of planet gears are rotatably arranged on a bearing pin about an axis of rotation, wherein the planet gear is supported on the bearing pin by a radial bearing and an axial bearing, and wherein the axial bearing is achieved by at least one bearing disk. Background of the invention

[0002] A planetary gear carrier arrangement of this type is known, for example, from DE 10 2012 216 235 A1 and from DE 10 2009 032 286 A1. The individual planetary gears in the arrangement are supported by a combined radial-axial bearing. In the first-mentioned solution, rolling bearings are provided for both the radial and axial bearings.

[0003] In a similar solution according to the generic DE 40 09 968 C2, a rolling bearing is used for the radial support of the planet gears; however, the axial support is designed as a sliding bearing, using bearing washers (thrust washers) arranged in the two axial end regions of the planet gear. A similar solution is shown in DE 10 2011 108 369 A1. In both cases, an anti-rotation device is provided for the bearing washers. In US 5 356 352 A, bearing washers are likewise used for the axial support, with these engaging axially in the planet gear with a double-bent, radially inner end region. A similar solution is shown in DE 195 40 118 A1.

[0004] Axial bearings, which are implemented using bearing discs, are often difficult to install, thus increasing assembly time and costs. Furthermore, when using bearing discs with a single-sided coating, there is a risk that the discs will not be installed in the correct orientation, leading to component failure after a short time.

[0005] JP 2010-255645A shows a radial needle roller bearing. This radial needle roller bearing, located between a pinion shaft and a pinion gear in a planetary gear mechanism of an automatic vehicle transmission, comprises: a pair of end sections provided at both axial ends; several columns intermittently arranged circumferentially between these two end sections, forming a holder that constitutes a pocket enclosed circumferentially by the adjacent columns and the two end sections; several needles freely rolling within each pocket; and a guide element that guides the holder. The end section of the holder has a conical surface that is guided by the guide element.

[0006] JP H05-223141A shows a bearing structure for a planetary gear drive. In this bearing structure, where a planet carrier supports the pinion gear, the planet carrier comprises a pinion shaft that supports the pinion gear and a carrier body that rigidly supports the pinion shaft. Several needle bearings are positioned between the outer surface of the pinion shaft and the inner surface of the pinion gear. Each needle bearing is held at a distance by a retainer located between the outer surface of the pinion shaft and the inner surface of the pinion gear. A thrust bearing washer is inserted between the side surface of the pinion gear and the side surface of the carrier body.The bearing structure of the pinion gear in the planetary gear unit is characterized by the fact that the locking section formed on the side edge of the needle bearing holder and the locking section formed on the inner edge of the axial bearing disk can engage and disengage in a state in which they are integrated.

[0007] DE 10 2012 210 694 A1 shows a thrust washer for a planetary gear bearing which interacts with a planetary gear pin via a central receptacle, wherein the thrust washer delimits a planetary gear on both sides which is rotatably mounted on the planetary gear pin which is fixed in position in a planetary gear carrier via a rolling bearing arrangement, wherein the rolling bearing arrangement comprises an inner ring via which a rolling bearing is indirectly guided on the planetary gear pin and the thrust washer is guided on an inner ring in the area of ​​the receptacle by at least two partially circumferential, perpendicularly aligned flange sections and includes alternately spaced radial recesses extending from the receptacle and aligned in the circumferential direction to the flange sections. Object of the invention

[0008] The present invention aims to further develop a generic planetary gear carrier arrangement in such a way that it is possible to ensure, in a simple and cost-effective manner, that the bearing disc can always be installed in the correct position. This is intended to stabilize the assembly process. In particular, it is intended to ensure that bearing discs coated on only one side are always installed in the correct position. Finally, it is intended to enable good centering of the bearing disc within the bearing arrangement in a simple manner. Summary of the invention

[0009] The solution to this problem by the invention is characterized in that the bearing disk has at least one axially extending projection along its circumference at a radially inner recess.

[0010] The radial bearing assembly comprises at least one needle roller assembly. The needle roller assembly comprises a cage. The cage has a radially inner surface designed to accommodate the at least one projection. This radially inner surface is a recess machined into the cage (or formed during the cage's manufacture).

[0011] After further development, the bearing disc has a coating on at least one side, preferably only one side. In this case, the correct positioning of the bearing disc is of particular importance.

[0012] The at least one projection is preferably formed from the material of the bearing disc by forming. Stamping and forming operations can be used in combination.

[0013] The at least one projection preferably extends from the base contour of the bearing disc by 90° in the axial direction.

[0014] The at least one projection can have a chamfer or lead-in chamfer at its axial end, which simplifies assembly. Similarly, the bearing pin can also have a chamfer or lead-in chamfer at its axial end.

[0015] Preferably at least two, and especially preferably three or four, projections are arranged on the bearing disc.

[0016] Thus, the invention is based on the fact that the bearing disc, which serves for axial support, is provided with at least one hook or a crank which is supported on the cage of the radial bearing or on the bolt and thus ensures good centering.

[0017] The proposed design provides an assembly-optimized arrangement that facilitates automation and ensures that the bearing discs used for axial support can only be installed in the correct position. This significantly simplifies the correct installation of the bearing disc.

[0018] The proposed design ensures that the bearing washer – especially if it only has a wear-resistant coating on one side – is always mounted in the correct position. Furthermore, it ensures that the bearing washer (thrust washer) is well centered within the bearing assembly, as it is radially supported either by the cage or the bearing pin.

[0019] The proposed planetary gear carrier arrangement is used in particular in a transmission device with a transfer case and a corresponding housing in which the transfer case is mounted. A carrier of the transfer case is rotatably mounted at at least one bearing point in the housing, the bearing being the aforementioned combined axial-radial bearing.

[0020] The bearing points for the spur gears on the distribution gearboxes or planetary gearboxes are preferably realized with a rolling element radial bearing and a sliding bearing axial bearing, as shown.

[0021] One preferred application is a planetary gear system, as is used particularly for electrically powered motor vehicles.

[0022] A particular embodiment of the invention relies on different centering diameters of the aforementioned projections (centering hooks). Although engagement of the aforementioned projections in the cage of the radial bearing is preferred, it can also be provided that the aforementioned projections bear against the bearing pin and thus fulfill the desired centering function. Brief description of the characters

[0023] The figures illustrate an embodiment of the invention. They show: Fig. 1 in radial section a planetary gear carrier arrangement, Fig. 2 the detail “A” according to Fig. 1, Fig. 3 in exploded view a planetary gear including bearings, Fig. 4 in perspective view a bearing disc of the bearing, Fig. 5 the detail “B” according to Fig. 4, Fig. 6 in perspective view the bearing disc of the bearing, seen from one side, and Fig. Figure 7 shows the bearing disc of the bearing in perspective, seen from the other side. Detailed description of the characters

[0024] In Fig. Figure 1 shows a planet carrier assembly 1 in which a number of planet gears 2 are mounted. The assembly 1 is used in a planetary gear unit, which need not be described in detail here. Reference is made in particular to the prior art mentioned at the beginning, where such gear units are described in sufficient detail.

[0025] Each planet gear 2 is supported in the planet carrier assembly 1, both axially a and radially r. The bearing used here consists of a bearing pin 3, which is fastened in the planet carrier assembly 1. In the exemplary embodiment, two radial bearings in the form of two needle roller bearings 4 and two axial bearings in the form of two bearing discs 5 are provided. The two bearing discs 5 are positioned in the two axial end regions of the planet gear 2.

[0026] The general structure of the bearing arrangement of the planet gears 2 can be seen from the exploded view according to Fig. 3 in more detail.

[0027] From the detailed presentation according to Fig. Figure 2 shows that the two needle rings 4 each have a cage 8 that guides the needles of the needle ring. The cage 8 has a radially inward-facing surface 9.

[0028] This surface 9 is designed to form a contact surface for a projection 7, several of which are formed on the bearing disc 5, which serves to center the bearing disc 5.

[0029] For this purpose, reference is made to the representation according to the Fig. 4 and Fig. 5. Reference is made to this. Here it can be seen that the bearing disc 5 has a radially internal recess 6. At three locations evenly distributed around the circumference, the aforementioned projections 7 are provided or formed, which are shaped from the material of the bearing disc 5 and extend in the axial direction a. This is shown again from the Fig. 6 and Fig. 7 stands out.

[0030] In the assembled position, as shown from the Fig. 1 and Fig. As can be seen in Figure 2, the bearing discs 5 are thus precisely centered on the cage 8. Furthermore, the bearing disc 5 can only be installed in the position shown; if the bearing disc 5 has a coating on only one side, it is therefore impossible for the bearing disc 5 to be installed in the wrong position.

[0031] From the Fig. 3 and Fig. Figure 5 shows that a chamfer or insertion ramp 10 can be provided on the projection 7 as well as a chamfer or insertion ramp 11 on the bearing bolt 3, which facilitates assembly. Reference symbol list 1 Planetary gear carrier arrangement 2 planetary gear 3 bearing bolts 4 Radial bearing (needle ring) 5 Axial bearing (bearing disc) 6 radially internal recesses of the bearing disc 7 lead 8 cage 9 radially inner surface of the cage 10 Chamfer / Lead-in chamfer on the projection 11 Chamfer / Lead-in chamfer on the bolt a axis of rotation / axial direction r radial direction

Claims

[1] Planetary gear carrier arrangement (1) of a planetary gear in which a number of planet gears (2) are rotatably arranged on each bearing pin (3) about an axis of rotation (a), wherein the bearing of the planet gear (2) on the bearing pin (3) is effected by a radial bearing (4) and an axial bearing (5) and wherein the axial bearing (5) is effected by at least one bearing disk (5), wherein the bearing disc (5) has at least one axially extending projection (7) along its circumference at a radially internal recess (6), wherein the radial bearing (4) comprises at least one needle roller bearing (4), wherein the needle roller bearing (4) comprises a cage (8), wherein the cage (8) has a radially inward surface (9) which is designed for the attachment of at least one projection (7), characterized by , that the radially inner surface (9) is a recess that is incorporated into the cage (8). [2] Planetary gear carrier arrangement (1) according to claim 1, characterized by that the bearing disc (5) has a coating at least on one side, preferably on only one side. [3] Planetary gear carrier arrangement (1) according to one of claims 1 or 2, characterized by , that the at least one projection (7) is formed from the material of the bearing disc (5) by forming. [4] Planetary gear carrier arrangement (1) according to any one of claims 1 to 3, characterized by , that the at least one projection (7) extends from the base contour of the bearing disk (5) by 90° in the axial direction (a). [5] Planetary gear carrier arrangement (1) according to any one of claims 1 to 4, characterized by, that the at least one projection (7) has a chamfer or lead-in chamfer (10) at its axial end and / or that the bearing pin (3) has a chamfer or lead-in chamfer (11) at its axial end. [6] Planetary gear carrier arrangement (1) according to any one of claims 1 to 5, characterized by that at least two, preferably three or four, projections (7) are arranged on the bearing disk (5).

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