Drive assembly with vents

Abstract

Drive assembly (1) with a connected oil chamber with at least two vents (3a, 3b), wherein one of the vents (3, 3b) is always located above the current oil level (6) in the oil chamber, depending on the inclination of the drive assembly (1).

Description

[0001] The invention relates to a drive assembly with a connected oil chamber with at least two vents. State of the art

[0002] Especially in gearboxes operating at high speeds, a significant amount of air enters the oil required for lubricating the gearbox components, resulting in the formation of oil foam. This condition is highly undesirable because this oil-air mixture does not ensure adequate lubrication of the gearbox parts. Therefore, venting systems are used to separate the air from the oil foam and then supply the separated oil to the gearbox components requiring lubrication.

[0003] Such a ventilation system for oil in a gearbox is known from DE 10 2017 114 889 A1. In this system, a settling chamber is equipped with various baffles so that the oil foam is forced through the settling chamber.

[0004] From DE 10 2021 207 712 A1, a drive assembly with a continuous oil chamber and at least two vents is known. The vents are arranged in the oil chamber such that, depending on the inclination of the drive assembly, one of the vents is located above the current oil level in the oil chamber.

[0005] Depending on the driving or operating conditions, but also due to the design (e.g., a separate oil tank), spaces can form within the system that contain a high oil level. If, for reasons of space or function, a vent is installed precisely in this area during the assembly's design, oil leakage can occur.

[0006] The purpose of the venting system is not to separate air from the oil-air mixture, but rather to equalize pressure within the gearbox and transmission system. Neither oil nor surface foam, i.e., the oil-air mixture, may escape above the oil level.

[0007] Additionally, the vent must not allow water or dirt to enter, which is often a problem due to the requirements of vehicle manufacturers regarding the vehicle's fording capability.

[0008] The purpose of the invention is to create a drive component that prevents oil leakage from the vent without effort. Description of the invention

[0009] The problem is solved with a drive assembly with a connected oil chamber with at least two vents, whereby one of the vents is always located above the current oil level in the oil chamber, depending on the inclination of the drive assembly.

[0010] The term drive assembly refers to gearboxes, gearbox components, transfer cases, electric machines, differentials, etc.

[0011] In terms of construction effort, the use of two vents is optimal, however it is also possible to install more than these two vents.

[0012] In an advantageous embodiment, a hose section is attached to each vent, which connect to form a vent hose, which is important in the case of a requirement for an increased wading level.

[0013] The hose is flexible, at least in part of its length.

[0014] The first vent is installed at the highest position of the drive assembly in its normal position.

[0015] The term "normal position" refers to a horizontal position of the vehicle and the resulting installation position of the drive assembly. Description of the characters Fig. Figure 1 shows a drive assembly in a horizontal driving position, Fig. Figure 2 shows the drive assembly in an inclined position.

[0016] As an example of a drive assembly 1, a differential 2a is chosen, which is provided with a side output shaft 2b as an example.

[0017] In the Fig. Figure 1 shows the differential 2a in a horizontal installation and driving position. During operation, the differential is covered with a layer of oil flung outwards by the rotating components. Only a small amount of oil is present above the side output shaft 2b, as the smooth design of the shaft limits its ability to carry away a significant amount of oil. There is a common oil reservoir.

[0018] This means that a high oil level is found at the first vent 3a, while a very low oil level is found at a second vent 3b.

[0019] With the use of the second vent 3b, pressure equalization takes place at the point with the lowest oil level.

[0020] Hose sections, a first hose section 4a and a second hose section 4b, are attached to the first vent 3a and the second vent 3b, respectively. The two hose sections join at a connection point 4c to form a vent hose 4.

[0021] The connection point 4c is located at a height h above the first vent 3a, the highest internal oil level 6.

[0022] The height h provides a sufficient distance to prevent oil escaping into the first hose section 4a from filling the entire venting area.

[0023] The venting takes place via the second hose section 4b into the vent hose 4.

[0024] The Fig.Figure 2 shows the differential 2a with the axle shaft 2b in an inclined position relative to the horizontal. Due to the inclined position, the oil flows from the upper part of the drive assembly 1 into the axle shaft 2b. This raises the first breather 3a significantly above the oil level. The second breather 3b, in turn, is located below the oil level. Thus, the drive assembly 1 is vented via the first breather 3a, with the distance h between the oil level and the connection point 4c of the breather hose 4 being greater than in horizontal operation.

[0025] The vent hose 4 with its two hose parts 4a and 4b is made of a flexible material.

[0026] The venting system does not require check valves.

[0027] An alternative embodiment can do without hose parts 4a and 4b and the vent hose 4.

[0028] Such an embodiment can be used if the oil level never reaches the first vent 3a under any driving condition. In that case, the distance h would not be defined by the distance of the connection point 4a of the vent hose 4 to the oil level, but rather by the distance of the first vent 3a to the oil level 6. The term "oil level" here also includes the level of the oil foam.

[0029] In such an embodiment, the position of the second vent 3b in relation to the first vent 3a is more critical than in the embodiment with the vent hose 4; the second vent is installed in a position that is best suited to create pressure equalization under certain driving conditions, so that the oil, for example, efficiently retreats from the installation point during a braking process. Reference sign 1 Drive assembly 2a Differential 2b Side shaft 3a upper vent 3b lower vent 4 hoses 4a Connection point 6 Oil level

Claims

[1] Drive assembly (1) with a connected oil chamber with at least two vents (3a, 3b), whereby one of the vents (3, 3b) is always above the current oil level (6) in the oil chamber, depending on the inclination of the drive assembly (1), characterized by that the first breather (3a) is installed at the position of the drive assembly (1) in its normal position, which becomes free of oil under certain driving conditions. [2] Drive assembly (1) according to claim 1, characterized by that a piece of hose (4a, 4b) is connected to each vent (3a, 3b), which connect to form a vent hose (4). [3] Drive assembly (1) according to claim 2, characterized by that the vent hose (4) is flexible at least over parts of its length. [4] Drive assembly (1) according to one of the preceding claims, characterized by that the first breather (3a) is installed at the highest position of the drive assembly (1) in its normal position.

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