Differential with sealed axle shaft gears and assembly method

Abstract

Differential (1) with one-piece carrier (2) with toothing (3), at least two planet gears (4) rotatably mounted on differential bolts (15) in the carrier (2), with axle side gears (5) to side shafts (6) of the drive axle of a vehicle, which mesh with the planet gears (4), wherein the axle side gears (5) are constructed in two parts from a bevel gear (7) and a sleeve (8) characterized in that the sleeve (8) has an internal splined connection (8b) which corresponds to a splined connection (6a) of the axle side shaft (6).

Description

[0001] The invention relates to a differential with a one-piece rotating carrier with teeth, at least two planet gears rotatably mounted on bolts or stars in the rotating carrier, with axle shaft gears to side shafts of the drive axle of a vehicle, which mesh with the planet gears. The invention also relates to an assembly method. State of the art

[0002] Currently known differentials consist of two planetary gears housed in a one-piece casing with side openings for mounting the planetary gears and secured with a single, inserted and locked bolt. The two planetary gears must handle the entire power transmission.

[0003] Alternatively, differentials with multiple planetary gears are known, which are inserted into the housing through an axial opening and can only be mounted using multi-part bolts. In this design, the planetary gears are supported only within the housing, and the differential is then closed with a side cover. Modern sealed differentials use bevel gears with extended necks to seal the transmission using a sealing ring. This extended neck makes the bevel gears significantly more complex to shape and machine. Furthermore, a split differential housing is required to mount them.

[0004] This means that these housing parts must be machined very precisely to fit each other and must also be joined together by a processing step such as welding or screwing.

[0005] DE 10 2008 015 694 A1 shows a differential gear with a housing, a pinion shaft, a pinion, an axle shaft wheel and an axle shaft.

[0006] From DE 10 2015 201 750 A1, a differential is known which has bevel gears with a sleeve. The sleeve is inserted into the bevel gear from the inside and has a recess for a seal. For positioning the sleeve, end-face lugs are provided which engage in recesses of the bevel gear.

[0007] From DE 10 2015 203 298 A1 a differential with a two-part bevel gear is known, wherein seals are used in a screwed section for sealing between sleeve and side gear.

[0008] The object of the invention is to create a compact, cost-effective, improved differential design that can be manufactured in one piece. Description of the invention

[0009] The problem is solved with a differential featuring a one-piece, toothed carrier, at least two planet gears rotatably mounted on differential bolts within the carrier, and axle side gears connecting to the side shafts of a vehicle's drive axle, which mesh with the planet gears. The axle side gears are constructed in two parts, consisting of a bevel gear and a sleeve. The sleeve has an internal splined connection that corresponds to a splined connection on the axle side shaft.

[0010] The two-part design allows for easy installation in the one-piece circular housing.

[0011] To seal the gearbox, each bevel gear has a circumferential groove that serves to accommodate an O-ring.

[0012] As anti-rotation devices, the sleeves have lugs on their front faces that serve to engage in recesses of the bevel gears.

[0013] The axle side shaft includes a snap ring that serves to connect it to the inner wall of the bevel gear.

[0014] The axle shaft has a stop on its outer diameter against which the sleeve comes to rest.

[0015] The task is solved using an assembly method for building a differential, whereby planet gears, differential bolts and bevel gears are mounted in the rotating basket, sleeves are pressed onto the bevel gears, and the axle side shafts are inserted into the bevel gears in the guide of the sleeves.

[0016] The assembly process is such that the sleeves are aligned with their noses to the recesses of the bevel gears before being pressed onto them.

[0017] The assembly procedure involves aligning the axle side shafts with respect to their splined connection to the splined connection of the sleeve. Description of the characters Fig. 1 and Fig. Figure 2 shows a section through a non-inventive embodiment of the differential, Fig. 3 and Fig. Figure 4 shows a first embodiment of an axle shaft gear, Fig. Figures 5 to 8 show a second embodiment not according to the invention, Fig. Figures 9 to 11 show an embodiment according to the invention. Fig. Figure 12 shows a section through a fully assembled differential in the design according to the invention with axle side shafts.

[0018] Fig. Figure 1 shows a differential 1 with a rotating carrier 2, which is supported on both sides against a vehicle via bearings. The rotating carrier 2 carries a toothed section 3, to which a drive gear on the vehicle side engages. Thus, the rotating carrier 2 is connected to the vehicle's driving motor.

[0019] The rotating carrier 2, which can be seen as a housing, is not designed to be divided into two parts. Planetary gears 4 are rotatably mounted on the differential bolt 15.

[0020] The planet gears 4 mesh with the two axle shaft gears 5 via a bevel gear. These each drive a side shaft 6.

[0021] The axle shaft gear 5 consists of a first part, the bevel gear 7, and a second part, a sleeve 8. The bevel gear 7 has bevel teeth 7b that engage with the teeth of the planet gears 4. On the side opposite the teeth, the bevel gear 7 has a circumferential groove 7a in which an O-ring 9 is received. The axial extension is formed by the sleeve 8, which supports the axle shaft 6 and, together with the bevel gear 7, provides the seal.

[0022] The sleeve 8 is made from a cost-effective pipe blank or a flow-formed part.

[0023] In Fig. Figure 4 shows the assembly of the axle shaft gear 5. The sleeve 8 is pushed over the extension piece 7d of the bevel gear 7 and fits snugly onto the circumference of the bevel gear and the O-ring 9.

[0024] When assembling with a simple press fit, there is a risk that the sleeves 8 will rotate relative to the bevel gear 7. In the Fig. Figures 5 to 8 describe an embodiment that provides anti-rotation protection. For this purpose, the sleeve 8 is provided with lugs 8a that extend axially along the outer wall of the sleeve 8 at its end face. These lugs 8a, in this embodiment there are three, engage in the corresponding recesses 7c on the bevel gear 7. On the side facing away from the teeth, the bevel gear 7 has a circumferential groove 7a in which an O-ring 9 is received. The sleeve 8 is again slid over the extension 7d of the bevel gear 7 and fits snugly against the circumference of the bevel gear and the O-ring 9.

[0025] In the Fig. Figures 9 to 11 illustrate an embodiment of the invention. This embodiment features a splined connection. The splined connection 8b is attached to the inner diameter of the sleeve on the sleeve side. The splined connection can be produced by embossing the tube.

[0026] The counterpart, the splined connection 6a, is located on the outside of the axle side shaft 6.

[0027] To prevent the tube of the sleeve 8 from migrating outwards, the axle side shaft 6 is provided with a stop 6b, which is provided as a step on the outer diameter of the axle side shaft 6.

[0028] As in the Fig. As shown in Figure 12, the axle side shaft 6 is fixed in the bevel gear 7 with a snap ring 6c.

[0029] For the assembly of the differential according to the invention, the conventionally manufactured bevel gear is mounted in the rotating carrier 2.

[0030] The sleeve 8 is then pressed onto the bevel gear with the O-ring 9. This creates the seal between the gearbox and the axle shaft. Reference sign 1 Differential 2 wheel carriers 3. Interlocking 4 planetary gears 5 Axle shaft wheel 6 Side shaft 6a Plug-in toothing 6b Attack 6c snap ring 7 bevel gear 7a Nut 7b Gearing 7c Exclusion 7d attachment 8 Sleeve 8a Nose 8b Splined connection 15 differential bolts

Claims

[1] Differential (1) with a one-piece carrier (2) with teeth (3), at least two planet gears (4) rotatably mounted on differential bolts (15) in the carrier (2), with axle side gears (5) to side shafts (6) of the drive axle of a vehicle, which mesh with the planet gears (4), wherein the axle side gears (5) are made up of two parts consisting of a bevel gear (7) and a sleeve (8). characterized by , that the sleeve (8) has an internal splined connection (8b) which corresponds to a splined connection (6a) of the axle side shaft (6). [2] Differential (1) according to claim 1, characterized by that the bevel gears (7) each have a circumferential groove (7a) which serves to accommodate one O-ring (9). [3] Differential (1) according to claim 1 or 2, characterized by , that the sleeve (8) has noses (8a) on its end face which serve to engage in recesses (7c) of the bevel gears (7). [4] Differential (1) according to any one of the preceding claims, characterized by, that the axle side shaft (6) includes a snap ring (6c) which serves to connect to the inner wall of the bevel gear (7). [5] Differential (1) according to any one of the preceding claims, characterized by , that the axle side shaft (6) has a stop (6b) on its outer diameter against which the sleeve (8) comes to rest. [6] Assembly method for constructing a differential (1) according to one of the preceding claims, wherein planet gears (4), differential bolts (15) and the bevel gears (7) are mounted in the rotating cage, wherein sleeves (8) are pressed onto the bevel gears (7), and the axle side shafts (6) are inserted into the bevel gears through the guidance of the sleeves (8). [7] Assembly method according to claim 6, wherein the sleeves are aligned with respect to their lugs (8a) to the recesses (7c) of the bevel gears (7) before being pressed onto the bevel gears (7). [8] Assembly method according to claim 6 or 7, wherein the axle side shafts (6) are aligned with respect to their splined connection (6a) to the splined connection (8b) of the sleeve (8).

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