Oil distribution disc for gearbox

Abstract

The invention relates to an oil distribution disc (30) for arrangement in an upper portion (3) in an oil-lubricated gearbox (2), the oil distribution disc (30) comprising a first chamber (10) comprising at least one oil distribution outlet (11) and a second chamber (20), the first chamber (10) for receiving oil and redistributing oil through the first chamber (10) via said at least one outlet (11), the second chamber (20) is used for being communicated with a ventilation device (4) of the gearbox (2).

Description

Technical Field

[0001] The invention relates to an oil distribution plate for a gearbox. The invention also relates to a gearbox comprising such an oil distribution plate. The invention also relates to a powertrain comprising such a gearbox or such an oil distribution plate. The invention also relates to a vehicle comprising such an oil distribution plate or such a gearbox or such a powertrain. Background Art

[0002] Vehicles, in particular electric vehicles or hybrid vehicles, usually include a gearbox designed to convert the rotational speed from the electric motor and / or the internal combustion engine into a rotational speed suitable for one or more drive wheels. Such gearboxes are lubricated with oil. Usually, such gearboxes include an oil reservoir, also called a reservoir. In most cases, the ring gear (such as the differential gear) splashes in the reservoir, thereby spraying the oil and lubricating the gearbox components.

[0003] Gearboxes of this type require ventilation to avoid pressure fluctuations, in particular excessive pressures, which are harmful and may lead to damage to the sealing lip. Such ventilation is usually achieved by grooves and / or ribs provided in the housing of such gearboxes to form a conduit between the interior and the exterior of such gearboxes. Obviously, such a conduit is shaped and / or arranged so that splashes of oil do not reach the conduit, or reach the conduit with difficulty.

[0004] However, the gearbox housing is usually obtained by casting and / or machining processes. Due to the complexity of its design and / or manufacturing, in particular using complex machining, expensive molds are required to produce such ventilation.

[0005] The production of one or more transmission housings with regard to ventilation can be conveniently simplified, in particular the production costs can be reduced. SUMMARY OF THE INVENTION

[0006] The object of the present invention is to provide an oil distribution plate that overcomes the above-mentioned disadvantages. In particular, the present invention proposes an oil distribution plate that participates in the ventilation function of the gearbox. Summary of the invention

[0007] To achieve this object, the present invention relates to an oil distribution plate, which is used to be arranged on the top of an oil-lubricated gear box, and the oil distribution plate comprises:

[0008] - a first chamber comprising at least one oil distribution outlet, said first chamber being adapted to receive oil and to redistribute the oil by draining it from said first chamber via at least one outlet,

[0009] - a second chamber, intended to communicate with the ventilation means of the gearbox.

[0010] The distribution plate may include a partition separating a first volume of the first chamber from a second volume of the second chamber to separate the first chamber for oil distribution from the second chamber for receiving or exhausting air.

[0011] The second chamber may include an air intake aperture to allow air to be supplied to the second chamber from within the gearbox.

[0012] The second chamber may include an oil drain orifice to remove any oil in the second chamber.

[0013] The oil distribution tray may be made of plastic and / or a composite material.

[0014] The invention also relates to an oil-lubricated gearbox, the gearbox comprising an upper part, the upper part comprising:

[0015] - an oil distribution plate as defined above,

[0016] - means for injecting oil into said upper part of said gearbox,

[0017] - ventilation means in the upper part of the gearbox,

[0018] The distribution plate is arranged such that the first chamber is opposite the injection device and the second chamber is opposite the ventilation device.

[0019] The distribution plate may comprise spacing means, in particular ribs, below the first chamber and / or below the second chamber in order to leave space for the oil to drain out of the oil drain opening of the second chamber.

[0020] The first chamber and / or the second chamber of the oil distribution plate may be completely open upward.

[0021] The gearbox includes a first housing and a second housing, and the first housing and the second housing are designed so that one of them is fixed on top of the other or the two are fixed relative to each other; the oil distribution plate is fixed on the first housing and / or the second housing, in particular, fixed by screws and / or centering pins and / or locating pins.

[0022] The gearbox may include a first housing and a second housing adapted to be fixed one on top of the other or fixed relative to each other, and the oil distribution plate is fixed in the gearbox by being wedged between the first housing and the second housing.

[0023] The invention also relates to a powertrain for a vehicle, in particular a motor vehicle, comprising a gearbox as defined above or an oil distribution plate as defined above.

[0024] The present invention also relates to a vehicle, in particular a motor vehicle, comprising a powertrain as defined above or a gearbox as defined above or an oil distribution plate as defined above. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] These objects, features and advantages of the present invention will be described in detail in the following description of a non-limiting embodiment of an oil distribution plate in relation to the accompanying drawings, in which:

[0026] Figure 1 It is a schematic diagram of a motor vehicle.

[0027] Figure 2 is a partial perspective view of a gearbox according to an embodiment of the present invention.

[0028] Figure 3 is another partial perspective view of a gearbox according to an embodiment of the present invention.

[0029] Figure 4 FIG. 1 is a top view of an oil distribution plate according to one embodiment of the present invention.

[0030] Figure 5 is a cross-sectional view of an oil distribution plate according to an embodiment of the present invention.

[0031] Figure 6 is a perspective view of an oil distribution plate according to an embodiment of the present invention.

[0032] Figure 7 is another perspective view of an oil distribution plate according to an embodiment of the present invention.

[0033] Figure 8 is another perspective view of an oil distribution plate according to an embodiment of the present invention.

[0034] Fig. 9 is another perspective view of an oil distribution plate according to an embodiment of the present invention. DETAILED DESCRIPTION

[0035] The direction in which a vehicle, in particular a motor vehicle, is moving in a straight line is defined as the longitudinal direction X. By convention, the direction perpendicular to the longitudinal direction, lying in a plane parallel to the ground, is called the transverse direction Y. The third direction perpendicular to these two directions is called the vertical direction Z. Therefore, we use a direct reference system XYZ, where X is the longitudinal direction of the vehicle in the forward-rearward direction (i.e. pointing to the rear), Y is the transverse direction pointing to the right, and Z is the vertical direction pointing upwards. The forward direction corresponds to the direction in which the vehicle usually moves in the longitudinal direction, opposite to the rearward direction.

[0036] Figure 1A vehicle 1 , preferably a motor vehicle, is schematically shown. The vehicle 1 comprises a powertrain 9 . The powertrain 9 comprises, for example, an electric motor and / or an internal combustion engine. The powertrain 9 or the vehicle 1 comprises a gearbox 2 .

[0037] The gearbox 2 is lubricated with oil. Figure 2 and Figure 3 The gearbox 2 is shown comprising an upper part 3. The term "upper part" refers to an area extending at the level of the highest point along the vertical direction Z of the gearbox, the gearbox being located in a vehicle parked on a surface substantially parallel to the XY plane.

[0038] The gearbox 2 also includes an oil distribution plate 30, which will be described later. The gearbox 2 also includes an oil injection device 5 located at the upper part 3 of the gearbox 2. For example, Figure 2 and Figure 3 As shown, the oil injection device 5 comprises, for example, a conduit bent at about 90 degrees. Such a conduit is preferably adapted to cooperate with a hose (not shown) conveying oil from the oil tank, the hose extending to the outside of the gearbox and / or to the inside of the gearbox. Alternatively, the rising oil circulates in a conduit formed in the gearbox housing, the conduit being obtained, for example, by machining or by casting. Advantageously, a pump (not shown), for example an electric pump, conveys the oil pumped or recovered from the oil pool to the conduit 5. As shown in FIG. Figure 3 As shown, the gearbox 2 preferably includes a boss 5B having a bore 5C to accommodate the conduit 5 .

[0039] The gearbox 2 also comprises a ventilation device 4 located in the upper part 3. The ventilation device 4 comprises, for example, a rigid conduit or a hose, usually called a "snorkel". In any case, the ventilation device is hollow to perform its function of supplying air to the interior of the gearbox or exhausting air from the interior of the gearbox according to the operating conditions. Figure 3 As shown, the gearbox 2 preferably comprises a boss 4B having a bore 4C to receive the conduit 4. Preferably, a shrunk-on spigot 4A is inserted into the bore, and the vent pipe is plugged or connected to the spigot 4A in a sealed manner.

[0040] Alternatively, a single boss is provided comprising two holes or bores, a first hole for oil inlet and a second hole for exhaust (embodiment not shown).

[0041] like Figure 2 and Figure 3 As shown, the oil distribution plate 30 is arranged in the upper part 3 of the gearbox 2 .

[0042] More specifically, the oil distribution plate 30 includes a first chamber or compartment or cavity 10. The first chamber 10 includes, defines, a first volume V1. The first chamber 10 includes at least one outlet 11 to allow oil to flow from the first chamber 10 to components of the transmission that require oil and receive little or no oil splashing. In other words, the first chamber 10 receives oil and distributes the oil through the at least one outlet 11. Figures 2 to 9 As shown, in the embodiment shown, three outlets 11 are provided in the first chamber 10. A single outlet, two outlets or more than three outlets may be provided in the first chamber. The number and position of the outlets in the first chamber should be adapted to the gearbox components and / or areas requiring oil lubrication. Advantageously, the outlet 11 is arranged at the lowest point of the volume V1 in the vertical direction Z so that all the oil in the first chamber 10 can be distributed. The oil is distributed by gravity.

[0043] The distribution plate 30 comprises a second chamber or compartment or cavity 20. The second chamber 20 comprises and defines a second volume V2. The second chamber 20 is intended to communicate with the ventilation device 4 of the gearbox 2. The second chamber 20 comprises an air intake aperture 21. Thus, the second chamber 20 comprises an air inlet from the interior of the gearbox 2 to the second chamber 20. Figure 4 , Figure 5 , Figure 7 , Figure 8 and Fig. 9 As shown, the second chamber 20 further includes an oil discharge orifice 22. Therefore, if oil remains in the second chamber 20, it is discharged through the oil discharge orifice 22.

[0044] The distribution plate 30 also includes a partition 31 separating the first volume V1 (volume of the first chamber 10) from the second volume V2 (volume of the second chamber 20). In other words, the first chamber 10 for oil distribution is separated from the second chamber 20 for receiving or exhausting air.

[0045] Preferably, if Figure 6 and Figure 7 As shown, the distribution plate 30 includes a spacer 32. For example, the spacer 32 is a rib, a protrusion or a projection extending from the lower outer surface 35 of the distribution plate. Therefore, preferably, the spacer 32 is arranged below the first chamber 10, for example close to the oil discharge orifice 22. Alternatively, the spacer is located below the second chamber 20. Alternatively, the spacer is arranged at the partition 31, extending between the two chambers, that is, arranged below the first chamber 10 and the second chamber 20. Due to the spacer 32, a space E is left between the lower outer surface 35 of the distribution plate and the inner wall or outer skin P of one or more gearbox housings 6, 7 (see Figure 5 ). In this way, the oil discharged from the oil discharge orifice 22 of the second chamber 20 returns to the oil tank by dripping downward along the wall P of one or more housings 6, 7. Figure 2In FIG. 6 , only the housing 6 is shown.

[0046] Preferably, the distribution tray 30 is made of plastic, for example by molding. Alternatively, the distribution tray 30 is made of a composite material. Alternatively, the distribution tray 30 includes plastic and a composite material. For example, the distribution tray is produced by 3D printing or a similar process.

[0047] Regarding the arrangement inside the gearbox, such as Figure 3 As shown, the distribution plate 30 is arranged so that the first chamber 10 faces the boss 5B accommodating the injection device 5 , while the second chamber 20 faces the boss 4B accommodating the ventilation device 4 .

[0048] Preferably, if Figure 3 , Figure 4 , Figure 5 , Figure 8 and Fig. 9 As shown, the distribution tray 30 is shaped such that the first chamber 10 and the second chamber 20 are completely open at the top.

[0049] Alternatively, the first and / or second chambers are partially open at the top. For example, the opening at the top of the first chamber 10 faces the ventilation device 4, and the opening at the top of the second chamber 20 faces the oil injection device 5 (not shown).

[0050] Preferably, the gearbox 2 comprises a first housing 6 and a second housing 7. The first housing 6 and the second housing 7 are fixed one on top of the other or fixed relative to each other. For example, the housings are held in place by screws or studs cooperating with nuts or bolts or by threaded holes cooperating with screws, particularly in the thicker portion 6S of the housing 6, such as Figure 2 shown.

[0051] For example, Figure 2 As shown, the distribution plate 30 is fixed to the first housing 6 by screws 8. For example, the threaded holes in the housing 6 allow the screws 8 to be screwed into the housing 6. In such a case, Figure 6 and Figure 7 As shown, the distribution plate 30 comprises fixing ears or brackets 36 in which holes or bores 37 are provided for the passage of the screws 8 .

[0052] Alternatively, the distribution disc is attached to the second housing 7, or may be connected to both housings. For example, at least one centering pin and / or at least one locating pin extends from the distribution disc, while an opening is provided in at least one housing to receive the pin or pins. For example, the locating pin is fir-tree shaped, i.e., generally conical, to facilitate its insertion while making it difficult to remove.

[0053] Alternatively, the distribution plate 30 is held in place within the gearbox 2 by being wedged, blocked, squeezed or encapsulated between the first housing 6 and the second housing 7. For example, the distribution plate further comprises one or more deformable tongues designed to bend when the two housings are closed or covered relative to each other to prevent any subsequent movement of the distribution plate within the gearbox.

[0054] It should be noted that the ventilation function is maximized by the presence of the holes 21 formed in the wall 23 of the second chamber 20 (see Figure 5 , Figure 7 and Figure 8 ). The hole 21 leads into the upper cavity C of the gearbox. In this way, the second volume V2 can be quickly emptied or filled with air according to the internal needs of the gearbox. Preferably, the oil distribution plate 30 is in contact with the top of the gearbox so that the gap J ( Figure 5 ) is zero or substantially zero. It should be reminded that the volume V1 (oil recovery) and the volume V2 (quiet zone) of the oil distribution plate 30 are preferably open at the top, so that the oil falls from the oil injection device 5 into the first volume V1, and the ventilation device 4 is directly connected to the volume V2.

[0055] As mentioned above, there is no gap J or only a minimal gap between the top of the distribution plate and the housing to prevent oil from entering the second chamber 20. Preferably, the second chamber 20 does not receive any oil. If this is the case, the oil drain orifice 22 allows the oil to drain quickly under the action of gravity. Preferably, the oil drain orifice 22 is located at the lowest point of the second chamber 20. The oil drain orifice 22 associated with the spacing device 32 ensures that any oil that "accidentally" enters the second volume V2 is drained. In other words, the oil drain orifice 22 ensures that the oil does not run off or overflow and destroy the function of the quiet zone. It should be reminded that the purpose of the quiet zone is to ensure communication between the interior of the gearbox and the external environment in order to obtain an internal pressure similar to atmospheric pressure.

[0056] Thanks to this solution, the second chamber 20 provides the second volume V2 as a minimum ventilation volume. In other words, in the event of a low pressure in the gearbox, the volume of air in the second volume and in the duct 4 is immediately available. Pressure equilibrium is immediately reached, which prevents any low pressure in the gearbox. In other words, the ventilation is optimal and the pressure remains constant in the gearbox. The lips of the seals or rings are not affected by pressure variations, which prevents their damage. Therefore, during operations that cause the gearbox to heat up, the gases can escape, thus preventing any excessive pressure that could damage the seals or the lip rings. Similarly, when cooling down (for example, wading or shutting down the internal combustion engine), air can enter the gearbox, thus avoiding negative pressure in the gearbox. The purpose of the ventilation function is to keep the gearbox at atmospheric pressure, which is optimal, in all operating phases.

[0057] Thanks to this solution, a simple boss 4B can be used to connect a conduit or pipe, ie a breather pipe, without using complex and expensive machining and / or grooves and / or ribs in the gearbox to prevent oil from spraying into the breather pipe or near its opening in the gearbox.

[0058] This solution makes it possible to combine two types of lubrication: on the one hand, lubrication of the gearbox by splashing, and on the other hand, dripping or flowing lubrication, under simple gravity, through discharge openings or orifices 11 provided in the disk 30. It should be recalled that the splashing occurs by the rotation of, for example, the annular differential gear, which lifts the oil from the sheet at the bottom of the gearbox and sprays it onto the parts to be lubricated, mainly the bearings. It should be recalled that the oil reaching the first chamber 10 via the injection device 5 is pumped from a tank or slick at the bottom of the gearbox.

[0059] It should be noted that pumped distribution or trickle lubrication is particularly suitable for hybrid transmissions, which use motors including bearings at a certain distance from the annular differential gear, for example. In addition, such bearings are subjected to very high rotational speeds, for example about 15000rpm, which requires a large supply of oil. The outlet 11 in the first chamber 10 can supply oil, for example, at the top (i.e. in an area that is difficult to splash). The oil is discharged precisely at the points where lubrication is required through the recovery disk or nozzle 30 by means of holes and / or nozzles and / or ramps and / or grooves and / or nozzles 11, which cannot be reached by splashing. These outlets 11 are advantageously oriented to guide the oil flow precisely to the components. In other words, the oil recovered by the pump is reintroduced into the gearbox through the opening 5 on the housing, as close as possible to the target lubrication area.

[0060] This solution enables the installation of an additional oil supply function for splash lubrication close to the ventilation function. It should be noted that the ventilation function is preferably located in the quiet zone of the gearbox. This solution is also compatible with the most complex gearbox structures (i.e. including motor-specific sensors, actuators and axes). In these complex structures, it is difficult to install ribs in the housing to form a quiet zone (i.e. an area not affected by oil splashes). However, the multifunctional channel solution 30 can be installed in such complex structures, thereby combining the oil recovery / redistribution and gearbox ventilation functions.

[0061] As previously mentioned, the distribution plate or chute 30 is advantageously securely and durably fixed relative to one or more gearbox housings, particularly once the gearbox is assembled. This eliminates any risk of the distribution plate becoming loose or moving relative to the gearbox.

[0062] In summary, the distribution plate combines two functions with opposite requirements in a single unit. This is achieved in the same area and in a particularly small space. As mentioned above, this replaces the need to create a quiet zone in the housing casting, which is very complex to achieve in the mold and expensive to design and manufacture. In addition, any machining required to obtain ribs to create the quiet zone is eliminated. It should be noted that said machining may be carried out at the same stage as the surface machining of the coupling face, which can generate vibrations affecting the flatness of the coupling face. Such machining problems are therefore avoided.

[0063] The distribution plate recovers the oil separately from the external flow, redistributes this oil to the components by gravity and creates a quiet zone inside the gearbox, preventing oil splashing, in contrast to external ventilation. Since the plate is particularly space-saving, these functions are grouped in a particularly small common area, which makes it easier to install in gearboxes with complex structures (including motors, for example). Preferably, the distribution plate is located in the upper part to follow the principle of gravity flow of the oil. Finally, if the gearbox is made of plastic, the distribution plate can easily implement these functions at a low cost.

[0064] The splash systems known from the prior art for gearbox components do not spray the oil to all the elements to be lubricated. Therefore, the oil is pumped up from the oil tank of the gearbox to a high point of such gearbox, usually by sucking the oil from such a tank by a pump. Thanks to the solution provided by the present invention, a device is created that makes the oil flow so high, which is arranged to distribute the oil to the elements that need lubrication, which the oil would not otherwise reach from splashing.

[0065] This solution thus achieves the desired goal of simplifying the manufacture of the gearbox housing ventilation and provides the following advantages:

[0066] -It can be used in transmissions of other types of vehicles, such as agricultural machinery, construction equipment, ships or other equipment (such as generators or pumps).

[0067] The shape of the distribution plate can be easily adapted to the internal configuration of any type of gearbox, in particular due to the complex shapes obtained due to its material.

Claims

1. An oil distribution plate (30) for arrangement in an upper part (3) of a gearbox (2) lubricated by oil, characterized in that: The oil distribution plate (30) comprises: - a first chamber (10) comprising at least one oil distribution outlet (11), said first chamber (10) being adapted to receive oil and to redistribute the oil by draining it from said first chamber (10) via the at least one outlet (11), - a second chamber (20) adapted to communicate with the ventilation device (4) of the gearbox (2).

2. The oil distribution plate (30) according to the preceding claim, characterized in that The distribution plate (30) includes a partition (31) which separates a first volume (V1) of the first chamber (10) from a second volume (V2) of the second chamber (20), so as to separate the first chamber (10) for distributing oil from the second chamber (20) for receiving or exhausting air.

3. The oil distribution plate (30) according to any one of the preceding claims, characterized in that The second chamber (20) comprises an air intake aperture (21) for allowing air to be supplied from the interior of the gearbox (2) to the second chamber (20).

4. The oil distribution plate (30) according to any one of the preceding claims, characterized in that The second chamber (20) includes an oil drain orifice (22) for draining any oil present in the second chamber (20).

5. The oil distribution plate (30) according to any one of the preceding claims, characterized in that The oil distribution plate (30) is made of plastic and / or composite material.

6. An oil-lubricated gearbox (2), the gearbox (2) comprising an upper part (3), the upper part (3) comprising: - an oil distribution plate (30) according to any one of the preceding claims, - injection means (5) for injecting oil into the upper part (3) of the gearbox (2), - a ventilation device (4) in the upper part (3) of the gearbox (2), The invention is characterized in that the oil distribution plate (30) is arranged so that the first chamber (10) faces the injection device (5) and the second chamber (20) faces the ventilation device (4).

7. A gearbox (2) according to the preceding claim in combination with claim 4, characterised in that The oil distribution plate (30) comprises spacer means (32), in particular ribs, located below the first chamber (10) and / or below the second chamber (20) to leave a space (E) for oil to be discharged from the oil discharge opening (22) of the second chamber (20).

8. The gearbox (2) according to claim 6 or 7, characterized in that: The first chamber (10) and / or the second chamber (20) of the oil distribution plate (30) is completely open at the top.

9. The gearbox (2) according to any one of claims 6 to 8, comprising a first housing (6) and a second housing (7), wherein one of the first housing (6) and the second housing (7) is fixed on top of the other or the two are fixed relative to each other, characterized in that: The oil distribution plate (30) is fixed to the first housing (6) and / or the second housing (7), in particular by means of screws (8) and / or centering pins and / or positioning pins.

10. The gearbox (2) according to any one of claims 6 to 8, comprising a first housing (6) and a second housing (7), wherein one of the first housing (6) and the second housing (7) is fixed on top of the other or the two are fixed relative to each other, characterized in that: The oil distribution plate (30) is fixed in the gearbox (2) by being wedged between the first housing (6) and the second housing (7).

11. A powertrain (9) for a vehicle, in particular a motor vehicle, characterized in that The powertrain (9) comprises a gearbox (2) according to any one of claims 6 to 10 or an oil distribution plate (30) according to any one of claims 1 to 5.

12. A vehicle, in particular a motor vehicle (1), characterized in that The vehicle comprises a powertrain (9) according to the preceding claim or a gearbox (2) according to any one of claims 6 to 10 or an oil distribution plate (30) according to any one of claims 1 to 5.

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