VEHICLE DRIVE TRAIN OF A VEHICLE

Abstract

The disclosure relates to a vehicle drive train of a vehicle comprising an engine which serves to drive at least one vehicle wheel, a multidisk brake assigned only to this driven vehicle wheel, and a clutch assigned only to this driven vehicle wheel, wherein the clutch is arranged between the engine and the vehicle wheel and, in the open state, decouples its associated vehicle wheel from the entire remaining vehicle drive train.

Claims

1. A vehicle drive train of a vehicle comprising an engine which serves to drive at least one vehicle wheel, a multidisk brake assigned only to this driven vehicle wheel, and a clutch assigned only to this driven vehicle wheel, wherein the clutch is arranged between the engine and the vehicle wheel and, in the open state, decouples its associated vehicle wheel from the entire remaining vehicle drive train.

2. The vehicle drive train according to claim 1, wherein the vehicle wheel, together with the multidisk brake and with that part of the vehicle drive train which is located between the vehicle wheel and the clutch, is decoupled from the entire remaining vehicle drive train when the clutch is open.

3. The vehicle drive train according to claim 1, wherein at least one driven vehicle axle is provided and a single, separate clutch is provided for each driven vehicle axle.

4. The vehicle drive train according to claim 1, wherein the clutch is arranged between a transmission assigned only to this vehicle wheel or only to one vehicle axle and the multidisk brake, directly between the vehicle wheel and the multidisk brake, or directly between the engine and the multidisk brake without the interposition of a transmission.

5. The vehicle drive train according to claim 1, wherein the clutch is provided between the transmission and a cardan shaft, or between the transmission and a drive shaft of the driven vehicle wheel, or in the transmission, or on a drive shaft of the driven vehicle wheel, or in a wheel hub of the driven vehicle wheel.

6. The vehicle drive train according to claim 1, wherein the clutch is provided on or in the transmission and the vehicle wheel with the multidisk brake and the part of the vehicle drive train from the vehicle wheel to the transmission or a part of a transmission is decoupled from the entire remaining vehicle drive train when the clutch is open.

7. The vehicle drive train according to claim 1, wherein the vehicle wheel is assigned to a vehicle axle which comprises a differential and a second driven vehicle wheel having a second multidisk brake assigned only to the second vehicle wheel, and wherein the differential spins and no force transmission can take place between the engine and the second vehicle wheel when the clutch is open.

8. The vehicle drive train according to claim 1, wherein the clutch is a frictionally engaged and/or a positive clutch.

9. The vehicle drive train according to claim 1, wherein the clutch is a positive clutch, a slipping clutch which slips when a defined torque is exceeded being integrated into the positive clutch.

10. The vehicle drive train according to claim 1, wherein an actuator is assigned to the clutch which serves to open and/or close the clutch and actuates the clutch hydraulically, pneumatically, electromechanically or electromagnetically.

11. The vehicle drive train according to claim 10, wherein a control means is provided which is set up to activate the actuator and controls the actuator depending on the driving state of the vehicle to cause an automatic opening and closing of the clutch.

12. The vehicle drive train according to claim 11, wherein the control means is programmed so as to cause an opening of the clutch during a braking process.

13. The vehicle drive train according to claim 12, wherein the control means is programmed so as to cause an opening of the clutch during a braking process in which there is no recuperation and/or during coasting of the vehicle.

14. The vehicle drive train according to claim 1, wherein the multidisk brake has an encapsulated multidisk brake housing, inner disks and outer disks which are accommodated in the encapsulated multidisk brake housing.

15. The vehicle drive train according to claim 14, wherein the multidisk brake is cooled by oil.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0053] FIG. 1 shows a schematic representation of a vehicle equipped with a vehicle drive train according to the disclosure in a plan view in accordance with a first option;

[0054] FIG. 2a shows a schematic representation of a vehicle drive train according to the disclosure in accordance with the first option with a clutch in the open state;

[0055] FIG. 2b shows a schematic representation of the vehicle drive train according to the disclosure in accordance with the first option with the clutch in the closed state;

[0056] FIG. 3 shows a schematic representation of the vehicle equipped with a vehicle drive train according to the disclosure in a plan view in accordance with a second option;

[0057] FIG. 4a shows a schematic representation of a vehicle drive train according to the disclosure in accordance with the second option with a clutch in the open state;

[0058] FIG. 4b shows a schematic representation of the vehicle drive train according to the disclosure in accordance with the second option with the clutch in the closed state;

[0059] FIG. 5 shows a schematic representation of a vehicle equipped with a vehicle drive train according to the disclosure in a plan view in accordance with a third option;

[0060] FIG. 6a shows a schematic representation of the vehicle drive train according to the disclosure in accordance with the third option with a clutch in the open state;

[0061] FIG. 6b shows a schematic representation of the vehicle drive train according to the disclosure in accordance with the third option with the clutch in the closed state;

[0062] FIG. 7 shows a schematic representation of a vehicle equipped with a vehicle drive train according to the disclosure in a plan view in accordance with a fourth option;

[0063] FIG. 8a shows a schematic representation of the vehicle drive train according to the disclosure in accordance with the fourth option with a clutch in the open state; and

[0064] FIG. 8b shows a schematic representation of the vehicle drive train according to the disclosure in accordance with the fourth option with the clutch in the closed state.

DETAILED DESCRIPTION

[0065] FIG. 1 shows a vehicle 10 having a vehicle drive train 12 according to a first option.

[0066] The vehicle drive train 12 comprises at least one engine 14 which serves to drive a vehicle wheel 16. According to FIG. 1, all four vehicle wheels 16 can also be driven by the engine. The engine can be an electric motor, an internal combustion engine or a hybrid drive engine.

[0067] The vehicle drive train 12 has a front axle 18, the driven vehicle wheels 16 of which are coupled to the engine 14 via drive shafts 20 connected to transmission outputs 21 of a transmission 22 arranged on the engine 14.

[0068] In addition, the vehicle drive train 12 according to FIG. 1 has a rear axle 24, the driven vehicle wheels 16 of which are coupled via drive shafts 26 to a transmission 28 designed as a differential, drive shafts 26 being connected to transmission outputs 30 of the transmission 28.

[0069] The transmission 28 also has a transmission input 32, which in turn is coupled to the transmission 22 arranged on the engine via a cardan shaft 34.

[0070] FIG. 1 shows only one possible configuration. It is basically also conceivable that only the front axle 18 or only the rear axle 24 comprises vehicle wheels 16 driven by the engine 14. Consequently, depending on the configuration, the one or other components of the vehicle drive train 12 described above are not absolutely necessary.

[0071] Furthermore, the vehicle drive train 12 comprises multidisk brakes 36, each of which is assigned to only one single driven vehicle wheel 16.

[0072] The multidisk brakes 36 each have a multidisk brake housing 38 and inner disks 40 and outer disks 42. The inner disks 40 and the outer disks 42 are accommodated in the encapsulated multidisk brake housing 38 (see FIG. 2). Furthermore, each multidisk brake 36 can be actuated hydraulically, pneumatically, electromechanically or electromagnetically to generate a braking force.

[0073] The multidisk brakes 36 are cooled by oil, for example.

[0074] Due to the encapsulated multidisk brake housing 38, abrasion, in particular abrasion in the form of particulates and fine dust from the inner disks 40 and/or the outer disks 42, remains inside the multidisk brake housing 38 when the multidisk brake 36 is actuated.

[0075] In addition, the vehicle drive train 12 comprises at least one clutch 44 respectively assigned to only one single driven vehicle wheel 16.

[0076] The clutch 44 can be a frictionally engaged clutch and/or a positive clutch.

[0077] If the clutch 44 is designed as a positive clutch, it is conceivable that a slipping clutch is integrated into the positive clutch, which slips when a defined torque is exceeded to prevent load peaks in the vehicle drive train 12.

[0078] An actuator 46 is provided to open and close the clutch 44 (see in particular FIGS. 2a, 2b). The clutch 44 can be actuated hydraulically, pneumatically, electromechanically or electromagnetically via the actuator 46.

[0079] In addition, a control means 48 is provided, which is coupled to the actuator 46 or 46 and is set up to activate the actuator 46. The activation takes place as a function of the driving state of the vehicle to cause an automatic opening and closing of the clutch 44, 44 by means of the actuator 46.

[0080] In FIG. 1, this clutch 44 is assigned to the driven left-hand vehicle wheel 16 of the rear axle 24. It is arranged between the engine 14 and the relevant driven vehicle wheel 16, so that in the open state, the clutch 44 decouples the associated driven vehicle wheel 16 from the remaining vehicle drive train 16.

[0081] Alternatively or additionally, such clutches 44 may also be assigned to each or only individual ones of the other driven vehicle wheels 16.

[0082] To illustrate this, a further clutch 44 is indicated in FIG. 1 by the dashed line, which is assigned to the driven left-hand vehicle wheel 16 of the front axle 18 as an example.

[0083] The interposition of the clutch 44 or 44 is shown schematically in FIGS. 2a and 2b.

[0084] FIG. 2a shows the clutch 44 or 44 in the open state. It is apparent therefrom that opening the clutch 44 or 44 results in the driven vehicle wheel 16, along with the multidisk brake 36 and the output-side part of the clutch 44 itself, being decoupled from the entire remaining vehicle drive train, i.e. in particular the transmission(s), which here can be the transmission 22 arranged on the engine and/or the transmission 28, and from the other components of the vehicle drive train 12, including the engine 14.

[0085] Closing the clutch 44 as shown in FIG. 2b in turn results in the driven vehicle wheel 16 and the multidisk brake 36 being coupled to the remaining part of the vehicle drive train. This is indicated by the additional arrow on the driven vehicle wheel 16 in FIG. 2b.

[0086] According to the first option, the clutch 44 or 44 is thus arranged, generally speaking, between a transmission assigned only to the driven vehicle wheel 16 and a transmission assigned to a vehicle axle 18, 24, which in this case may be the transmission 22 or 28 arranged on the engine 14, and a multidisk brake 36 arranged on the vehicle wheel 16.

[0087] The exact positioning of the clutch 44 or 44 can be selected differently.

[0088] It is thus conceivable to provide the clutch 44 or 44 between the transmission 28 and the drive shaft 26 or between the transmission 22 arranged on the engine 14 and the drive shaft 20 of the respective driven vehicle wheel 16.

[0089] The clutch 44 or 44 itself can be provided directly at the respective transmission output 21 or 30 on the outside of the respective transmission 22 or 28 or can be provided in the transmission 22 or 28, i.e. the housing. Thus, when the clutch 44 or 44 is open, the respective driven vehicle wheel with the part of the vehicle drive train from the vehicle wheel itself to the transmission 22 or 28 is decoupled from the entire remaining vehicle drive train.

[0090] Alternatively, it is also conceivable that the clutch is provided on the drive shaft 20 or 26 of the respective driven vehicle wheel 16.

[0091] Furthermore, it is also conceivable to provide the clutch 44 or 44 in the wheel hub of the respective driven vehicle wheel 16 (not shown in FIG. 1), so that when the clutch 44 or 44 is open, the vehicle wheel 16 along with the multidisk brake 36 is already decoupled from the remaining vehicle drive train from the drive shaft 20 or 26.

[0092] If a setup according to FIG. 1 is selected, in which only one single clutch 44 or 44 is arranged on the front axle 18 and/or on the rear axle 24 and the drive shafts 20 or the drive shafts 26 are connected to the transmission outputs 21 or 30 of a transmission designed as a differential, it is possible for the driven vehicle wheel 16 to be decoupled from the entire remaining vehicle drive train when the clutch 44 or 44 is open and that the transmission 22 or 28 designed as a differential spins and no force transmission can take place between the engine 14 and the respective second vehicle wheel 16 on the front axle 18 and/or on the rear axle 24.

[0093] FIGS. 3 to 4b show a vehicle drive train 12 according to a second option. In contrast to the previous option, the clutch 44 of the second option is positioned between the transmission 28 and the cardan shaft 34. The explanations given above for the first option can generally be applied analogously to the second option.

[0094] Accordingly, as also shown in FIG. 4a, when the clutch 44 is open, the vehicle wheel 16 with the multidisk brake 36 and the part of the vehicle drive train 12 from the vehicle wheel 16 to the transmission 28 or to at least part of the transmission 28 would be decoupled from the remaining vehicle drive train when the clutch is open.

[0095] The decoupling of the driven vehicle wheels 16 on the rear axle 24 from each other is effected by the transmission 28, which is designed as a differential and which spins in case of a relative speed difference between the driven vehicle wheels 16.

[0096] FIGS. 5 to 6b show a vehicle drive train 12 according to a third option. Here, both the front axle 18 and the rear axle 24 each have an engine 14 and thus also driven vehicle wheels 16. However, it is also conceivable that only one of the vehicle axles 18, 24 comprises driven vehicle wheels 16. As already mentioned for option 2, the explanations given above for the first option can generally be applied analogously to the second option.

[0097] In this third option, the clutch 44 or 44 is arranged directly between the engine 14 and the multidisk brake 36 of the respective driven vehicle wheel 16 without the interposition of a transmission.

[0098] In FIG. 5, only one clutch is arranged on the front axle 18 and on the rear axle 24, each of which is assigned to only one driven vehicle wheel 16 of the vehicle axles 18, 24.

[0099] However, it is also possible that a clutch 44 or 44 is assigned to both driven vehicle wheels 16 of the front axle 18 or rear axle 24.

[0100] According to FIG. 6a, when the clutch 44 is open, the driven vehicle wheel 16, along with the associated multidisk brake 36 and a part of the clutch 44 itself, is decoupled from the entire remaining vehicle drive train, which consists in particular of the drive shafts 20 or 26 and the engine 14.

[0101] The operation of the clutch 44 and/or 44 of the first to third options will be explained below.

[0102] In accordance with the above explanations, the control means 48 is intended to activate the actuator 46 on the basis of the driving state and to cause an automatic opening and closing of the clutch 44 and/or 44.

[0103] To this end, the control means 48 is programmed so as to cause an opening of the clutch 44 and/or 44 during a braking process, so that the respective driven vehicle wheel 16 to which the clutch 44 and/or 44 is assigned is decoupled from the entire remaining vehicle drive train with the multidisk brake 36 and the part of the vehicle drive train from the respective driven vehicle wheel 16 up to the open clutch. As a result, the moments of inertia acting through the rotating masses do not act during the braking process, so that the braking force which must be applied by the multidisk brake 36 can be lower than if the clutch 44 and/or 44 were closed.

[0104] If recuperation takes place during the braking process in electric vehicles, for example, or if the engine is used as an engine brake in a vehicle having an internal combustion engine, it is also conceivable that the control means 48 does not open the clutch 44 and/or 44 as long as recuperation or braking by the engine takes place.

[0105] Furthermore, the control means 48 can also be programmed so as to cause the clutch 44 and/or 44 to open when the vehicle 10 is coasting, so that any losses, for example due to friction in the vehicle drive train 12, do not affect the respective driven vehicle wheel 16.

[0106] In addition to the previously discussed options 1 to 3, which are shown in FIGS. 1 to 6b, the vehicle drive train 12 according to the fourth option, which is shown in FIGS. 7 to 8b, is explained below.

[0107] In contrast to all previous options, the clutch 44 in the fourth option is provided directly on the driven vehicle wheel 16, so that opening the clutch 44 results in a decoupling of the vehicle wheel 16 from the entire vehicle drive train, including the multidisk brake 36.

[0108] Apart from this, the explanations given above for the first option apply to the exclusion of the operation of the clutch.

[0109] In contrast to the previous options, in the vehicle drive train 12 according to the fourth option, the clutch 44 must be closed during a braking process, so that the driven vehicle wheel 16 is coupled to the associated multidisk brake 36 and a braking force can be transmitted from the multidisk brake 36 to the driven vehicle wheel 16.

[0110] Accordingly, in the fourth option, the control means 48 must activate the actuator 46 if the clutch 44 is in the open state and a braking process is to be initiated.

[0111] This process must take place extremely quickly so that there is no time delay when a braking process is to be initiated.

[0112] Automatic opening by activating the actuator 46 via the control means 48 could then take place if the vehicle is in a coasting mode and the driven vehicle wheel 16 is not to be braked by resistance, such as friction in the vehicle drive train 12.

[0113] In the embodiments shown, at least one driven vehicle axle is provided and one single, separate clutch is provided for each driven vehicle axle, which is inserted into the drive train such that it can be used to decouple all driven wheels of this vehicle axle from the drive. This is possible, for example, by arranging the clutch upstream of the differential or downstream of the differential and in a partial train between the differential and one of the two drive wheels.