Oil supply circuit of a gearbox assembly

Abstract

An oil supply circuit for a vehicle's transmission assembly is proposed, comprising at least one first oil supply chamber (1) with rotating components (3) and a first oil volume (4). The first oil supply chamber (1) has a first oil drain (8) substantially tangentially in the direction of oil flow on the inner wall region of the first oil supply chamber (1), which is connected via an oil drain channel (9) to a second oil supply chamber (2) with a second oil volume (5). At least one pump (6) is assigned to the second oil supply chamber (2) for the common oil supply, which supplies the first oil supply chamber (1) with a predetermined oil delivery volume depending on the rotational speed range of the components (3) from the second oil supply chamber (2). The first oil supply chamber (1) is also assigned at least one second oil drain (11).whose drain opening (12) is arranged radially closer to an axis of rotation (14) of the components (3) in the first oil supply chamber (1) than the first oil drain (8) for oil volume equalization between the first oil supply chamber (1) and the second oil supply chamber (2).

Description

[0001] The present invention relates to an oil supply circuit of a transmission arrangement for a vehicle according to the type defined in more detail in the preamble of patent claim 1.

[0002] For example, a lubrication device for a transmission is known from the publication DE 10 2015 217 893 B3. Further lubrication devices for a transmission are known, for example, from the documents US 4,630,711 A and DE 10 2010 004 222 A1. The lubrication device has a central lubrication bore, which is designed as an oil-carrying axial bore through a shaft, into which several radial bores of the shaft open. A tube is inserted into each radial bore. To adjust the volume flow flowing out through the radial bores, each of the tubes has a slot at its end facing a central axis of the shaft, which slot extends along a central axis of the respective tube in the interior of the axial bore. The slot geometry limits the amount of lubricant supplied via the shaft to the components arranged outside the shaft to a predefined maximum value.

[0003] Furthermore, the use of a so-called shared oil supply system is known, particularly in oil supply circuits of transmission arrangements for all-wheel drive applications. In the shared oil circuit, the oil is pumped from the all-wheel drive transfer case housing into the oil supply chamber of the front axle differential housing by an oil pump. From there, it flows back to the oil supply chamber of the all-wheel drive transfer case housing. This shared oil supply system offers advantages in terms of lubrication, temperature, and efficiency. The pump for supplying the two oil supply chambers is assigned to the transfer case and has a fixed gear ratio to the front axle differential. This results in different oil supply flows depending on the speed or the speed of the front axle differential. Depending on the driving conditions, this can lead to an imbalance between oil inflow and oil outflow.In addition, conditions occur during extended uphill journeys, where gravity creates additional effects that disrupt the volume balance. When driving uphill, more oil tends to flow away, so the oil volume in the front axle differential housing tends to decrease. When driving downhill, the oil flows away less effectively, so the oil volume in the front axle differential housing increases, but there is no oil in the transfer case housing. This oil volume imbalance has disadvantages in terms of efficiency and temperature rise due to splashing losses if the oil volume is too large, and disadvantages such as insufficient lubrication and cooling if the oil volume in the respective oil supply chambers is too small.

[0004] The present invention is based on the object of proposing an oil supply circuit of a transmission arrangement of the type described above, in which an oil volume compensation between the oil supply chambers is ensured.

[0005] This object is achieved according to the invention by the features of patent claim 1, wherein advantageous and claimed developments result from the subclaims and the description as well as the drawings.

[0006] Thus, an oil supply circuit of a transmission arrangement of a vehicle with at least one first oil supply chamber with rotating components with a first oil volume is proposed, wherein the first oil supply chamber has a first oil outlet substantially tangential in the oil flow direction on the inner wall region of the first oil supply chamber, which is connected via an oil outlet channel to a second oil supply chamber with a second oil volume, to which at least one pump is assigned for the common oil supply, which pump supplies the first oil supply chamber with a predetermined oil delivery volume depending on the respective speed range of the components from the second oil supply chamber.In order to ensure oil volume equalization and thus a comparatively uniform oil drainage quantity between the oil supply chambers, it is provided that at least one second oil drain or the like is assigned to the first oil supply chamber, the drain opening of which is arranged radially closer to a rotational axis of the components of the first oil supply chamber than the first oil drain.

[0007] In order to ensure oil volume compensation regardless of the speed and inclination of the vehicle in the oil supply circuit according to the invention, the drain opening of the second oil drain is spaced radially from the inner wall region of the first oil supply chamber in such a way that the drain opening is arranged outside an oil ring volume formed when a predetermined medium speed range is reached and below an increased oil level formed in the first oil supply chamber when a predetermined low speed range is reached and / or at a predetermined inclination of the vehicle.

[0008] In this way, in the oil supply circuit according to the invention, at least one further outflow for the oil is provided, the drain opening of which is located radially closer to the pivot point of the components in the first oil supply chamber, so that this additional oil drain only becomes active once the oil ring volume has developed a certain radial thickness at the circumferential region or on the inner wall region. Only when the oil ring volume reaches the drain opening due to a larger oil flow into the first oil supply chamber due to higher speeds and thus increasing pump power, is an additional oil flow generated through the second oil drain from the first oil supply chamber into the oil drain channel. As a result, the increased oil volume in the first oil supply chamber is immediately reduced again.Furthermore, the oil drain opening is arranged in such a way that it is associated with the bottom region of the first oil supply chamber, so that even at low speeds, oil from the increasing oil volume can flow out of the first oil supply chamber through the oil drain opening of the second oil drain due to the non-development of the oil ring volume. Consequently, the second oil drain also achieves volume equalization at low speeds, since the oil drain opening of the second oil drain is arranged below the elevated oil level in the first oil supply chamber.

[0009] Within the scope of an advantageous embodiment of the present invention, the second oil drain is designed as a pipe connected to the oil drain channel, which extends radially into the first oil supply chamber with a predetermined length or with the drain opening. Thus, the optimal arrangement position of the oil drain opening of the second oil drain in the first oil supply chamber can be realized in a structurally simple manner.

[0010] However, it is also conceivable for the second oil drain to be designed as a bore or the like extending in the housing of the first oil supply chamber, one end of which is connected to the oil drain channel and the other end of which is designed such that it projects radially into the first oil supply chamber. The end projecting into the first oil supply chamber may also possibly be designed with a sleeve or the like.

[0011] In a particularly preferred application of the proposed oil supply circuit, it is provided that the first oil supply chamber is designed as a front axle differential housing, wherein the speed of the rotating components corresponds to the speed of the front axle differential, and that the second oil supply chamber is designed as an all-wheel transfer case housing.

[0012] The invention is further explained below with reference to the drawings. They show: Fig. 1 is a schematic view of a possible embodiment of an oil supply circuit according to the invention for a transmission arrangement of a vehicle at a medium speed range of the rotating components or at a medium speed of the vehicle; and Fig. 2 a schematic view of the oil supply circuit at low engine speed or low vehicle speed.

[0013] In the Fig. 1 and Fig. 2 shows, by way of example, a possible embodiment variant of an oil supply circuit according to the invention of a transmission arrangement of a vehicle at different speed ranges of the vehicle.

[0014] The proposed oil supply circuit comprises a first oil supply chamber 1 as the front axle differential housing and a second oil supply chamber 2 as the all-wheel drive distributor housing. Rotating components 3 of the front axle differential are assigned to the first oil supply chamber 1 and are supplied with a first oil volume 4 for cooling and lubrication. A second oil volume 5 is assigned to the second oil supply chamber 2 or the distributor gearbox. At least one pump 6 is assigned to the second oil supply chamber 2 or the distributor gearbox for the common oil supply. This pump 6 supplies the first oil supply chamber 1 with a predetermined oil delivery volume from the second oil supply chamber 2 via a supply channel 7, depending on the speed range of the components of the front axle differential. The pump 6 is drive-connected to the front axle differential via a fixed gear ratio.

[0015] A first oil outlet 8 is assigned to the first oil supply chamber 1, essentially tangential in the oil flow direction on the inner wall region of the first oil supply chamber 1, which is connected to the second oil supply chamber 2 via an oil drain channel 9. The first oil outlet 8 is usually designed as a bore and is connected to the oil drain channel 9. The first oil outlet 8 is arranged at a predetermined angle so that it is arranged approximately tangentially in the oil flow direction. Due to the rotation of the components 3 in the front axle differential, such as a ring gear and a differential carrier, the oil is moved in the direction of rotation and forms an oil volume ring 10 above a predetermined speed range, so that the oil is discharged from the first oil supply chamber 1 into the first oil outlet 8.

[0016] In order to achieve oil volume compensation in all speed ranges, it is provided that a second oil drain 11 is assigned to the first oil supply chamber 1 or the front axle differential housing, the drain opening 12 of which is spaced radially from the inner wall region of the first oil supply chamber 1 in such a way that the drain opening 12 is arranged outside the oil ring volume 10 formed at a predetermined medium speed range and below an increased oil level 13 in the first oil supply chamber 1 for oil volume compensation between the two oil supply chambers 1, 2 when a predetermined lower speed range is reached and / or at a predetermined inclination of the vehicle-formed oil level.

[0017] Accordingly, in addition to the oil drain 8, which is aligned approximately tangentially to the direction of oil flow and opens below the axis of rotation 14 of the components 3 of the front axle differential in the first oil supply chamber 1, from which the oil returns to the intake area of ​​the pump 6, the additional second oil drain 11 is provided in the first oil supply chamber 1, which, viewed radially, opens closer to the axis of rotation 14 of the components 3 in the first oil supply chamber 1, so that in all operating states a comparatively uniform amount of oil drains from the first oil supply chamber 1 back into the second oil supply chamber 2 or into the sump.

[0018] As can be seen from the Fig. 1 and Fig.As can be seen from Figure 2, the first oil drain 8 is provided as a bore in a housing part 15, which opens into the oil drain channel 9. In the embodiment shown, the second oil drain 11 is designed as a pipe connected to the oil drain channel 9, which projects radially into the first oil supply chamber 1 with its outlet opening 12.

[0019] This results in a first operating range that corresponds to the predetermined low speed range of the components 3 in the first oil supply chamber 1 or a low speed range of the vehicle. In this first range, the oil ring volume 10 has not yet formed, so that only a small oil flow flows through the first oil outlet 8 from the first oil supply volume 1. However, because the second oil outlet 11 is arranged below the raised oil level 13 in the first oil supply chamber 1, an additional oil flow is discharged through the second oil outlet 11. Consequently, an oil volume equilibrium is established between the inflow and outflow from the first oil supply chamber 1, so that the first oil volume 4 and the second oil volume 5 are approximately constant.

[0020] In a second operating range, which corresponds to the predetermined average speed range of the components 3 in the first oil supply chamber 1 or a medium speed range of the vehicle, the oil ring volume 10 is already formed on the peripheral region or in the interior region of the first oil supply chamber 1. The oil flowing into the first oil supply chamber 1 can thus flow out through the first oil drain 8. As more oil flows into the first oil supply chamber 1 and the oil ring volume 10 thus increases and reaches the drain opening 12 of the second oil drain 11, the outflow of oil from the first oil supply chamber 1 through the second oil drain 11 is increased. Consequently, the oil inflow and oil outflow are in balance, so that the first oil volume 4 and the second oil volume 5 are approximately constant in this range as well.

[0021] In a third operating range, which corresponds to the predetermined high speed range of the components 3 in the first oil supply chamber 1 or a high speed range of the vehicle, the oil ring volume 10 is also formed, as in the medium speed range, so that the oil to be flowed into the first oil supply stream 1 can flow out of the first oil supply chamber 1 both through the first oil outlet 8 and through the second oil outlet 11, so that the first oil volume 4 and the second oil volume 5 are again balanced or constant. Reference symbol 1 first oil supply chamber or front axle differential housing 2 second oil supply chamber or all-wheel drive transfer case housing 3 rotating components of the front axle differential 4 first oil volume 5 second oil volume 6 Pump 7 supply channel 8 first oil drain 9 Oil drain channel 10 oil ring volume 11 second oil drain 12 Drain opening of the second oil drain 13 increased oil level 14 Axis of rotation of the rotating components of the front axle differential 15 Housing part

Claims

[1] Oil supply circuit of a transmission arrangement of a vehicle with at least one first oil supply chamber (1) with rotating components (3) with a first oil volume (4), wherein the first oil supply chamber (1) has a first oil outlet (8) substantially tangential in the oil flow direction on the inner wall region of the first oil supply chamber (1), which is connected via an oil outlet channel (9) to a second oil supply chamber (2) with a second oil volume (5), to which at least one pump (6) is assigned for the common oil supply, which pump supplies the first oil supply chamber (1) with a predetermined oil delivery volume depending on the speed range of the components (3) from the second oil supply chamber (2), characterized bythat at least one second oil drain (11) is assigned to the first oil supply chamber (1), the drain opening (12) of which is arranged, viewed radially, closer to a rotational axis (14) of the components (3) in the first oil supply chamber (1) than the first oil drain (8) for oil volume compensation between the first oil supply chamber (1) and the second oil supply chamber (2). [2] Oil supply circuit according to claim 1, characterized by that the drain opening (12) of the second oil drain (11) is spaced radially from the inner wall region of the first oil supply chamber (1) in such a way that the drain opening (12) is arranged outside an oil ring volume (10) formed when a predetermined medium speed range is reached and below an increased oil level (13) formed when a predetermined lower speed range is reached and / or at a predetermined inclination of the vehicle in the first oil supply chamber (1). [3] Oil supply circuit according to claim 1 or 2, characterized by that the second oil drain (11) is designed as a pipe connected to the oil drain channel (9), which projects radially into the first oil supply chamber (1) with the drain opening (12). [4] Oil supply circuit according to one of claims 1 to 3, characterized by that the second oil drain (11) is designed as a bore extending in a housing part (15) of the first oil supply chamber (1), one end of which is connected to the oil drain channel (9) and the other end of which is designed such that it projects radially into the first oil supply chamber (1). [5] Oil supply circuit according to one of the preceding claims, characterized by that the first oil supply chamber (1) is designed as a front axle differential housing, wherein the speed of the rotating components (3) corresponds to the speed of the front axle differential and that the second oil supply chamber (2) is designed as an all-wheel transfer case housing. [6] Oil supply circuit according to claim 5, characterized by that at a predetermined low speed range of the front axle differential, no oil ring volume (10) is provided, so that an increased oil level (13) is provided at the bottom region of the front axle differential housing, wherein the oil from the front axle differential housing flows essentially through the second oil drain (11) into the all-wheel transfer case housing, so that the first oil volume (4) and the second oil volume (5) are balanced. [7] Oil supply circuit according to claim 4 or 5, characterized bythat at medium speed range of the front axle differential, the oil ring volume (10) is provided, wherein the oil from the front axle differential housing flows essentially through the first oil outlet (8) into the all-wheel transfer case housing, and when higher speed ranges of the front axle differential are reached, additional oil flows via the second oil outlet (11) into the front axle differential housing, so that the first oil volume (4) and the second oil volume (5) are balanced.

Images