TRANSMISSION FOR A COMMERCIAL VEHICLE WITH A TRANSMISSION HOUSING WITH A VENTING ARRANGEMENT

Abstract

A transmission for a commercial vehicle that has a transmission housing in which at least one venting arrangement, for equalizing the pressure between an inside space of the transmission housing and the surroundings of the transmission housing, is provided. The arrangement includes a vent fixed on a wall of the transmission housing on the surroundings side. The vent is connected by way of an oil foam reducing venting channel to at least one inside space of the transmission housing. At least a first venting bore, on the inside space side, and a second venting bore, on the vent side, are provided as the venting channel such that, in relation to their cross-sections, the venting bores are offset relative to one another, at their connection area, in such manner that a step-shaped transition is formed in the connection area between the venting bores.

Claims

1-11. (canceled)

12. A transmission for a commercial vehicle comprising: a transmission housing (1) in which at least one venting arrangement (2) is provided for pressure equalization between at least one inside space of the transmission housing (1) and a surrounding of the transmission housing (1), the venting arrangement having a vent (8) fixed on a wall (7) of the transmission housing (1) on a surroundings side, the vent being connected by at least one oil foam reducing venting channel to the at least one inside space of the transmission housing (1), and at least one first venting bore (9), on an inside space side, and a second venting bore (10), on a vent side, are provided as the venting channel such that at a connection area (14) thereof, in relation to their cross-sections, the first and the second venting bores (9, 10) are offset relative to one another in such manner that a step-shaped transition (11) is formed at the connection area (14) between the first and the second venting bores (9, 10).

13. The transmission according to claim 12, wherein the first venting bore (9) passes through an intermediate plate (4) and the second venting bore (10) passes through a flange area in the wall (7) of the transmission housing (1).

14. The transmission according to claim 13, wherein the connection area (14) of the first and the second venting bores (9, 10) is located on the flange area of the wall (7) of the transmission housing (1) that faces toward the intermediate plate (4).

15. The transmission according to claim 12, wherein at least one peripheral edge around at least one of an inside diameter of a capture area (15) and an end area (16) of the first venting bore (9) has a sharp-edge in order to reduce the oil foam.

16. The transmission according to claim 15, wherein an edge angle of the at least one peripheral edge is around 90.

17. The transmission according to claim 12, wherein the first and the second venting bores (9, 10) have different diameter geometries.

18. The transmission according to claim 13, wherein the first venting bore (9) opens into an intermediate space (5) in which oil is not agitated, the intermediate space is spatially separated by an intermediate plate (4) from a gearing space (3) which is flushed with oil and which, for venting purposes, communicates with the gearing space (3).

19. The transmission according to claim 18, wherein the intermediate space (5) is designed as a power take-off space.

20. The transmission according to claim 12, wherein at least the first venting bore (9) follows a suitable path for oil return purposes.

21. The transmission according to claim 12, wherein the second venting bore (10) extends approximately horizontally and a vertically orientated connection for the vent (8) is arranged after the second venting bore (10).

22. A commercial vehicle with a transmission comprising a transmission housing (1) in which at least one venting arrangement (2) is provided for pressure equalization between at least one inside space of the transmission housing (1) and a surrounding of the transmission housing (1), the venting arrangement having a vent (8) fixed on a wall (7) of the transmission housing (1), on a surrounding side, the vent is connected by at least one oil foam reducing venting channel to the at least one inside space of the transmission housing (1), and at least one first venting bore (9), on an inside space side, and a second venting bore (10), on a vent side, are provided as the venting channel such that at a connection area (14) thereof, in relation to their cross-sections, the first and the second venting bores (9, 10) are offset relative to one another in such manner that a step-shaped transition (11) is formed at the connection area (14) between the first and the second venting bores (9, 10).

23. A transmission for a commercial vehicle, the transmission comprising: a transmission housing (1) having at least one venting arrangement (2) for equalizing pressure between an interior of the transmission housing (1) and an exterior of the transmission housing (1); the venting arrangement (2) having a vent (8) fixed on an exterior side of a wall (7) of the transmission housing (1), the vent being connected, via at least one oil foam reducing venting channel, to at least one interior space of the transmission housing (1); the venting channel comprises a first venting passage (9), located on an interior side of the venting channel, and a second venting passage (10), located on a vent side of the venting channel, the first and the second venting passages being connect to each other at a connection area (14), and a cross-section of the first venting channel and a cross-section of the second venting channel are offset relative to each other such that a step-shaped transition (11) being formed at the connection area (14) between the first and the second venting channels (9, 10).

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Below, the present invention is explained further with reference to the drawings, which show:

[0017] FIG. 1: A schematic, sectioned view of a possible embodiment variant of a transmission according to the invention with a venting arrangement; and

[0018] FIG. 2: Schematically, a detailed sectioned view according to FIG. 1.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0019] In FIGS. 1 and 2 a possible embodiment variant of a transmission of a vehicle, in particular a commercial vehicle is shown as an example, the transmission having a transmission housing 1 in which at least one venting arrangement 2 is provided for equalizing the pressure between an inside space of the transmission housing 1 and the surroundings of the transmission housing 1. The transmission shown as an example is a transmission for any type of commercial vehicle, such as a pickup or some other special vehicle which needs at least one power take-off in order to be able to tap off appropriate drive power for a hydraulic system or the like.

[0020] The transmission housing 1 shown as an example has essentially three functional spaces on its inside. First there is an oil-flushed gearing space 3 in which the transmission gearing with the shifting elements are accommodated. In addition, an intermediate space 5 separated from the gearing space 3 by an intermediate plate 4 is provided, which for venting purposes communicates with the gearing space 3 but in which the oil is not agitated. Connected to the intermediate space 5 is the so-termed converter space for the torque converter of the transmission.

[0021] The venting arrangement 2 of the transmission comprises a vent 8 attached on the wall of the transmission housing 1, which connects the surroundings of the transmission to the inside space of the transmission housing 1 by way of an oil foam reducing venting channel.

[0022] In order to produce a venting arrangement 2 as simply designed and as inexpensive as possible, it is provided that as the venting channel a first venting bore 9 on the inside space side and a second venting bore 10 on the vent side are provided, wherein the venting bores 9, 10 in their connection area 14, relative to their cross-section, are offset with respect to one another in such manner that a step-shaped transition 11 is provided at the connection area 14 between the venting bores 9, 10. At this step-shaped transition 11 the oil is separated from the incoming oil foam, so that the oil can flow back into the oil sump of the transmission housing 1.

[0023] As can be seen in particular in the detailed view shown in FIG. 2, the first venting bore 9 passes through the intermediate plate 4 and the second venting bore passes through a flange area in the wall 7 of the transmission housing 1. The connection area 14 of the two venting bores 9, 10 is on the flange area of the wall 7 of the transmission housing 1 that faces toward the intermediate plate 4. By virtue of the arrangement of the two venting bores 9, 10 offset in relation to their cross-sections, the step-shaped transition 11 is formed.

[0024] The oil foam reduction or separation of the oil from the oil foam is further improved in that on the peripheral edges extending around the inside diameter, or inner peripheral edge, both in the capture area 15, i.e. at the inlet opening, and also the end area 16, i.e. at the outlet opening of the first venting bore 9, the edges are made sharp. Since the end area 16 of the first venting bore 9 corresponds to the connection area 14 of the venting bores 9, 10, the step-shaped transition 11 is also sharp-edged. The edge angle of the respective peripheral edges can amount to around 90. This breaks down the oil foam bubbles and the oil is separated out.

[0025] Owing to the different diameter geometries of the first venting bore 9, which for example has a smaller diameter, and the second venting bore 10, which for example has a larger diameter, the creep speed of the oil foam varies, whereby the oil separation is further improved so that the oil-free venting of the transmission is optimized.

[0026] Since the first venting bore 9 opens into the intermediate space 5 in which the oil is not agitated, which space is separated by the intermediate plate 4 from the gearing space 3 which is flushed with oil, the amount of oil foam that can make its way into the first venting bore 9 is reduced further.

[0027] In a particularly advantageous manner, the intermediate space 5 is designed as a power take-off space which is already present in a commercial vehicle in order to be able to accommodate the power take-off.

[0028] Furthermore, it can be seen from FIG. 2 that the first venting bore 9 is shaped suitably for the return of oil. For example the second venting bore 10 extends horizontally, so that the vertically arranged vent 8 can be positioned after the horizontally extending second venting bore 10. Thanks to this horizontal path it is ensured that only air can emerge through the vent 8 arranged vertically relative to it for pressure equalization purposes. In the embodiment variant illustrated, the vent 8 is made with a press-on casing 12 which is positioned in a bore that opens into the second venting bore 10. The press-on casing 12 holds a sieve insert 13.

INDEXES

[0029] 1 Transmission housing [0030] 2 Venting arrangement [0031] 3 Gearing space [0032] 4 Intermediate plate [0033] 5 Intermediate space [0034] 6 Converter space [0035] 7 Wall [0036] 8 Vent [0037] 9 First venting bore [0038] 10 Second venting bore [0039] 11 Step-shaped transition [0040] 12 Press-on casing [0041] 13 Sieve insert [0042] 14 Connection area [0043] 15 Capture area of the first venting bore [0044] 16 End area of the first venting bore