AGRICULTURAL UTILITY VEHICLE HAVING A POWER TAKEOFF AND METHOD FOR OPERATING THE POWER TAKEOFF

Abstract

An agricultural utility vehicle includes a working power takeoff drivable by means of an internal combustion engine for operating an implement. The utility vehicle further includes an auxiliary power takeoff, which can be driven by an energy storage device and is coupled to the working power takeoff in such a manner that the working power takeoff is additionally driven at least transiently by the auxiliary power takeoff.

Claims

1. Agriculture utility vehicle, comprising: an internal combustion engine; an implement; an energy storage device; a working power takeoff operably driven by the internal combustion engine in order to operate the implement; and an auxiliary power takeoff operably coupled to and driven by the energy storage device, wherein the auxiliary power takeoff is coupled to the working power takeoff such that the working power takeoff is at least transiently driven by the auxiliary power takeoff.

2. The vehicle of claim 1, wherein the auxiliary power takeoff is operably functional as an additional drive during an elevated load torque or during a load torque peak at the working power takeoff.

3. The vehicle of claim 1, wherein the energy storage device comprises an energy storage unit for storing kinetic energy from the auxiliary power takeoff.

4. The vehicle of claim 3, wherein the energy storage device comprises a flywheel mass.

5. The vehicle of claim 3, wherein the energy storage device comprises an electrical energy storage unit.

6. The vehicle of claim 5, wherein the energy storage device comprises an electrical machine operably connected to the electrical energy storage unit and the auxiliary power takeoff.

7. The vehicle of claim 6, wherein the electrical machine comprises a motor function and a generator function.

8. The vehicle of claim 1, wherein the working power takeoff is constructed as a rear power takeoff and the auxiliary power takeoff is constructed as a front power takeoff.

9. The vehicle of claim 1, wherein the energy storage device is arranged on or in a three-point hitch.

10. The vehicle of claim 1, wherein the implement is designed as a large baler.

11. A method for driving a working power takeoff of an agricultural utility vehicle, comprising: providing an internal combustion engine, an implement, an energy storage device, and an auxiliary power takeoff; operably driving the working power takeoff by the internal combustion engine; controllably operating the implement by the working power takeoff; operably driving the auxiliary power takeoff by the energy storage device; coupling the working power takeoff to the auxiliary power takeoff; and at least partially driving the working power takeoff in a transient manner by the auxiliary power takeoff.

12. The method of claim 11, further comprising: determining an operating information item of the implement in operation; and depending on the operating information item, defining a time or a period of time in which the working power takeoff is operably driven by the auxiliary power takeoff.

13. The method of claim 10, wherein the implement is designed as a large baler.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The above-mentioned aspects of the present disclosure and the manner of obtaining them will become more apparent and the disclosure itself will be better understood by reference to the following description of the embodiments of the disclosure, taken in conjunction with the accompanying drawings, wherein:

[0023] FIG. 1 shows an agricultural utility vehicle with a schematically illustrated implement at its rear;

[0024] FIG. 2 shows a schematic-like representation of a working system consisting of the utility vehicle and the implement of FIG. 1; and

[0025] FIG. 3 shows the front region of the utility vehicle of FIG. 1.

DETAILED DESCRIPTION

[0026] In FIG. 1, an embodiment of an agricultural utility vehicle 10 is in the form of a tractor having a cab, a front axle 14, and an internal combustion engine 16 for driving at least a rear axle 18. An implement 20 is operated with respect to its working function by means of a rear power takeoff (hereinafter working power takeoff 22) and is present at the rear area of the utility vehicle 10. A front three-point hitch 24, which supports a removable energy supply device 26, is present at the front end of the utility vehicle 10. The energy storage device 26 has the purpose of driving a front power takeoff (hereinafter auxiliary power takeoff 28).

[0027] In the region of the cab 12 there is an operating element 30 for activating and deactivating the working power takeoff 22 and an operating element 32 for activating and deactivating the auxiliary power takeoff 28, among other things. In addition, an appropriate transmission ratio can be preselected and the power takeoff rotational speed can be limited by means of the operating elements 30, 32.

[0028] FIG. 2 schematically shows individual details of the interaction of the utility vehicle 10 with the implement 20. The two power takeoffs 22, 28 can be driven by a suitable gearbox device 34 and the drivetrain of the utility vehicle independently of one another by the internal combustion engine 16.

[0029] The auxiliary power takeoff 28 can additionally be coupled via the gearbox device 34 to the working power takeoff 22 in such a manner that the auxiliary power takeoff 28 simply runs at the speed of the working power takeoff 22, which is achieved by the driving of the working power takeoff 22 by the internal combustion engine 16. In addition, the auxiliary power takeoff 28 can be coupled in an assistance mode to the working power takeoff 22 in such a manner that, at defined times or periods of time, the working power takeoff 22 is not driven only by the internal combustion engine 16, but also by the auxiliary power takeoff 28, in order to compensate for elevated load torques or load torque peaks at the working power takeoff 22.

[0030] In FIG. 2, an implement 20 in the form of a large baler 36 is operated by means of the working power takeoff 22. The big baler 36 includes a flywheel 38 which, optionally via intervening additional components for transmitting force, is drivingly coupled to the working power takeoff 22. A pressing gear unit 40, which operates a pressing piston 42, is connected to the flywheel 38. Depending on the design, additional components for force transmission (not shown) can be provided between the flywheel 38, the pressing gear unit 40 and the pressing piston 42.

[0031] The energy storage device 26 according to FIG. 2 contains an alternating current machine 44 that can be used as a motor and a generator, an AC/DC converter 46, an energy storage unit 48 designed as a super-capacitor, and a control unit 50. The control unit 50 is connected via a data bus 52 of the utility vehicle 10 to a control unit 54 of the implement 20 or the large baler 36. In this way, the control unit 50 of the energy storage device 26 can receive data and information regarding expected load cycles of the implement 20 or the large baler 36. The energy storage device can be controlled in such a manner that the alternating current machine 44 is active as a generator during a low-load period of time (e.g., with torques M of approximately M.sub.N), so that mechanical energy available at the auxiliary power takeoff is stored as electrical energy in the energy storage unit 48. During the elevated load or peak load generated by the implement 20 or the large baler 36 (e.g., in the period t.sub.1 to t.sub.2), the alternating current machine 44 operates as a motor and outputs the stored energy back to the auxiliary power takeoff 28, which thereby additionally drives the drive shaft 22 in an assistance mode. The control unit 50 regulates the torque of the alternating current machine 44 operating as a motor, based on received or determined predictive load information from the implement 20 or the large baler 36.

[0032] Due to the pressing piston 42 in the large baler 36, high cyclical peak loads, i.e., torques M that are greater than a low-load torque M.sub.N and can reach a peak torque M.sub.S (see schematic diagram in FIG. 1) are generated and can be transmitted via the pressing gear unit 40 to the working power takeoff 22 of the utility vehicle 10. This can lead to a decrease of the rotational speed of the internal combustion engine 16 and a decrease of the forward speed of the utility vehicle 10 in working operation. In order to compensate for the elevated loads or peak loads, the working power takeoff 22 is additionally driven by the auxiliary power takeoff 28 at defined times or periods of time (e.g., t.sub.S, or t.sub.1 to t.sub.2). For this purpose, an information item of the active big baler 36 is determined in the embodiment according to FIG. 2. This operating information item can be a position P.sub.K and a pressing force F.sub.P of the pressing piston 42, for example. On the basis of this information, predictive load information is determined, particularly a load torque M to be expected or a load peak M>M.sub.N and the associated time t.sub.1, t.sub.S, t.sub.2 or time period t.sub.1 to t.sub.2. It is thereby possible to define times or periods of time in which the auxiliary power takeoff 28 is coupled to the working power takeoff 22 and supplied with kinetic energy in such a manner that the working power takeoff 22 is additionally driven by the auxiliary power takeoff 28.

[0033] While the energy storage device 26 according to FIG. 2 can be considered an electrically active flywheel mass or electrically active flywheel, the energy storage device 26 in the embodiment of FIG. 3 has a mechanical flywheel mass 56 that is connected to the auxiliary power takeoff 28.

[0034] While embodiments incorporating the principles of the present disclosure have been described hereinabove, the present disclosure is not limited to the described embodiments. Instead, this application is intended to cover any variations, uses, or adaptations of the disclosure using its general principles. Further, this application is intended to cover such departures from the present disclosure as come within known or customary practice in the art to which this disclosure pertains and which fall within the limits of the appended claims.