Method for mounting a milling unit of a ground milling machine, and ground milling machine comprising a dismountable and mountable milling unit

1. A method for dismounting and mounting a milling unit of a ground milling machine for alignment of a releasable milling unit relative to a machine frame of a ground milling machine, comprising the steps:

a) using a first alignment device for rough alignment of the milling unit relative to the machine frame; and

b) using a second alignment device for fine alignment of the milling unit relative to the machine frame,

the rough alignment in step a) and the fine alignment in step b) being effected by moving the ground milling machine relative to the ground.

2. The method according to claim 1 ,

wherein in step a) the ground milling machine is moved relative to the milling unit in or against a forward direction of advance along wedge surfaces extending horizontally inclined relative to a longitudinal axis of the ground milling machine.

3. The method according to claim 1 ,

wherein a swinging of the milling unit suspended from the machine frame is effected in step a).

4. The method according to claim 3 ,

wherein the swinging comprises the following steps:

establishing a flexible suspension connection between the milling unit and the machine frame of the ground milling machine;

lifting the ground milling machine and swinging the milling unit suspended from the machine frame; and

lowering the ground milling machine onto the milling unit.

5. The method according to claim 1 ,

wherein in step b) the ground milling machine is vertically adjusted relative to the milling unit by lowering the machine frame of the ground milling machine onto the milling unit.

6. A ground milling machine, comprising:

a machine frame;

a drive engine;

travelling devices driven by the drive engine which are connected to the machine frame via height-adjustable lifting columns; and

a milling unit comprising a milling drum for milling the ground material and a milling drum box for covering the milling drum to the sides and upward, the milling unit being fastened to the machine frame of the ground milling machine via a fastening device in a detachable manner,

wherein a first and a second alignment device are present which are designed for alignment of the milling unit relative to the machine frame for fastening the milling unit to the machine frame, the first and the second alignment device being configured differently.

7. The ground milling machine according to claim 6 ,

wherein the first and the second alignment device each have means on the milling unit and on the machine frame which are configured such that they interact with one another for alignment purposes to get into abutment.

8. The ground milling machine according to claim 6 ,

wherein the first and/or the second alignment device are form fit devices.

9. The ground milling machine according to claim 6 ,

wherein the first alignment device has wedge surfaces acting essentially in the horizontal direction.

10. The ground milling machine according to claim 6 ,

wherein the first alignment device has vertically protruding form fit wedge wall elements, and that counter elements for abutment to the wedge wall elements are present, the form fit elements being arranged on the machine frame and the counter elements being arranged on the milling unit, or vice versa.

11. The ground milling machine according to claim 10 ,

wherein the wedge wall elements are arranged in opposing pairs on the longitudinal sides of the ground milling machine and the horizontal distance of their wedge walls tapers in or against the forward direction of advance of the ground milling machine.

12. The ground milling machine according to claim 6 ,

wherein the first alignment device includes a flexible suspension connection between the milling unit and the ground milling machine.

13. The ground milling machine according to claim 12 ,

wherein the first alignment device is a suspension swing via which the milling unit can be suspended from the machine frame of the ground milling machine.

14. The ground milling machine according to claim 6 ,

wherein the second alignment device comprises wedge surfaces essentially acting in the vertical direction.

15. The ground milling machine according to claim 10 ,

wherein the second alignment device comprises trunnions or teeth standing vertically with their longitudinal axes, and receptacle bores or receptacle recesses as counter elements, the trunnions or teeth being arranged on the machine frame and the receptacle bores respectively receptacle recesses being arranged on the milling unit, or vice versa.

16. The ground milling machine according to claim 15 ,

wherein the vertical height of the vertically protruding form fit elements is greater than the vertical height of the trunnions or teeth.

17. The ground milling machine according to claim 6 ,

wherein the first alignment device and the second alignment device are arranged functionally in series.

18. The ground milling machine according to claim 6 ,

wherein the milling drum box is connected to the machine frame via a quick coupling system which can be operated by being locked and unlocked from the operator platform, and/or in that a connection block for simultaneous connection of multiple fluid and/or supply connections between the milling unit and the ground milling machine is present.

19. The method according to claim 5 ,

wherein the machine frame of the ground milling machine is lowered onto the milling unit along wedge surfaces with vertically extending longitudinal axes.

20. The ground milling machine according to claim 8 ,

wherein the first and/or the second alignment device are form fit devices with slide surfaces.

21. The ground milling machine according to claim 20 ,

wherein the slide surfaces are in the form of conical and/or wedge surfaces.

22. The ground milling machine according to claim 12 ,

wherein the flexible suspension connection is in the form of ropes, chains or straps.