Roller groups for grinding devices, grinding devices, and methods

1. A roll assembly ( 10 ) for a milling apparatus ( 70 ) comprising:

a first roll ( 11 ), which is held by at least one first bearing body ( 13 ), and a second roll ( 12 ),

which is held by at least one second bearing body ( 14 ),

wherein the first bearing body ( 13 ) and the second bearing body ( 14 ) are adjustable relative to one another in such a way that a milling gap formed, between the first roll ( 11 ) and the second roll ( 12 ), is adjustable,

the first bearing body ( 13 ) and the second bearing body ( 14 ) are pretensionable with respect to one another by means of a tensioning device ( 16 ) in such a way that the first roll ( 11 ) and the second roll ( 12 ) are pressed towards one another,

the first bearing body ( 13 ) has at least one first abutment body ( 17 ) with a first abutment surface ( 18 ), and the second bearing body ( 14 ) has at least one second abutment body ( 19 ) with a second abutment surface ( 20 ),

the abutment surfaces ( 18 , 20 ) are formed and are or can be arranged on the bearing bodies ( 13 , 14 ) in such a way that a contact of the abutment surfaces ( 18 , 20 ) counteracts a contact of the rolls ( 11 , 12 ),

the first abutment body ( 17 ) is rotatable about a first axis of rotation (A 1 ), and the first abutment surface ( 18 ) is formed by a circumferential surface ( 18 ) of the first abutment body ( 17 ) that is eccentric with respect to the first axis of rotation (A 1 ), with the result that the rotational position of the first abutment body ( 17 ) determines the minimum width of the milling gap; and

wherein the second abutment body ( 19 ) is rotatable about a second axis of rotation (A 2 ) which is parallel to the first axis of rotation (A 1 ), and the second abutment surface ( 20 ) is formed by a circumferential surface ( 20 ) of the second abutment body ( 19 ) that is rotationally symmetrical with respect to the second axis of rotation (A 2 ).

2. The roll assembly ( 10 ) according to claim 1 , wherein the first axis of rotation (A 1 ) of the first abutment body ( 17 ) and/or the second axis of rotation (A 2 ) of the second abutment body ( 19 ) are/is arranged displaceably.

3. The roll assembly ( 10 ) according to claim 1 , wherein the roll assembly ( 10 ) has a handwheel ( 21 ) which can be rotated about a handwheel axis of rotation (H) and which is coupled via a handwheel gear mechanism ( 22 ) to the first abutment body ( 17 ) in such a way that a rotation of the handwheel ( 21 ) causes a rotation of the first abutment body ( 17 ).

4. The roll assembly ( 10 ) according to claim 1 , wherein the roll assembly ( 10 ) has a force-measuring device which comprises:

a first sensor ( 24 ) for directly or indirectly determining a first force with which the first bearing body ( 13 ) and the second bearing body ( 14 ) are pretensioned with respect to one another;

a second sensor ( 25 ) for directly or indirectly determining a second force which acts between the first abutment body ( 17 ) and the second abutment body ( 19 ).

5. The roll assembly ( 10 ) according to claim 3 , wherein the roll assembly ( 10 ) has a position indicator ( 26 ) for indicating a position of the handwheel ( 21 ), and the position indicator ( 26 ) comprises a position indicator housing ( 27 ) and an indicator element ( 28 ) which is movable along the handwheel axis of rotation (H) relative to the position indicator housing ( 27 ) and which is or can be pretensioned by means of a position indicator spring ( 29 ) in the direction of the handwheel axis of rotation (H) with respect to the position indicator housing ( 27 ) in such a way that it can be rotated about the handwheel axis of rotation (H) only upon overcoming the pretensioning brought about by the position indicator spring ( 29 ).

6. The roll assembly ( 10 ) according to claim 1 , wherein the roll assembly ( 10 ) has an integrated rolling device ( 30 ) having at least one roller ( 31 ) which is or can be arranged on the roll assembly ( 10 ) in such a way that the roll assembly ( 10 ) can be placed onto a horizontal base relative to a ground floor and moved thereon by the at least one roller ( 31 ).

7. The roll assembly ( 10 ) according to claim 1 , wherein at least one of the bearing bodies ( 13 , 14 ) has a rolling bearing ( 58 ) which supports a roll stub ( 33 ) of one of the rolls ( 11 , 12 ), a bearing cover ( 63 ) of the rolling bearing ( 58 ) has on its inner side ( 34 ) a guide channel ( 35 ) for lubricant that extends around the roll stub ( 33 ) and is connected to an outlet opening ( 36 ) through which lubricant can exit the guide channel ( 35 ).

8. The roll assembly ( 10 ) according to claim 1 , wherein the first roll ( 11 ) is held by two first bearing bodies ( 13 ), the second roll ( 12 ) is held by two second bearing bodies ( 14 ), and the first bearing bodies ( 13 ) are adjustable independently of one another and/or the second bearing bodies ( 14 ) are adjustable independently of one another.

9. A milling apparatus ( 70 ), comprising a machine stand ( 71 ) and at least one roll assembly ( 10 ) according to claim 1 that is or can be inserted in the machine stand ( 71 ).

10. The milling apparatus ( 70 ) according to claim 9 , wherein the machine stand ( 71 ) has a tensioning device ( 16 ), and the roll assembly ( 10 ) has a coupling device ( 66 ) which is arranged in particular on the second bearing body ( 14 ) and intended for releasably coupling the roll assembly ( 10 ) to the tensioning device ( 16 ).

11. The milling apparatus ( 70 ) according to claim 9 , wherein the tensioning device ( 16 ) has a cylinder ( 40 ).

12. A milling apparatus ( 70 ) according to claim 9 , wherein the tensioning device ( 16 ) has at least one pretensioned spring ( 41 ).

13. The milling apparatus ( 70 ) according to claim 9 , wherein the roll assembly has an integrated rolling device ( 30 ) having at least one roller ( 31 ) which is or can be arranged on the roll assembly ( 10 ) in such a way that the roll assembly can be placed onto a horizontal base relative to a ground floor and moved thereon by means of the at least one roller ( 31 ), and

the machine stand ( 71 ) has at least one rail ( 72 ) on which the at least one roller ( 31 ) of the roll assembly ( 10 ) is movable during mounting and/or demounting of the roll assembly ( 10 ), the roll assembly ( 10 ) has at least one contact surface ( 42 , 76 ) and the machine stand ( 71 ) has at least one counter-contact surface ( 73 ), and the contact surface ( 42 , 76 ) and the counter-contact surface ( 73 ) are tailored to one another and to the at least one rail ( 72 ) in such a way that, in a mounted position of the roll assembly ( 10 ) in the machine stand ( 71 ), by virtue of at least one form-fitting engagement between the at least one contact surface ( 42 , 76 ) and the at least one counter-contact surface ( 73 ), the at least one roller ( 31 ) of the roll assembly ( 10 ) does not lie on the rail ( 72 ).

14. A method for determining the radial force acting between the rolls ( 11 , 12 ) of a roll assembly ( 10 ) according to claim 4 , comprising calculating the radial force acting between the rolls ( 11 , 12 ) from forces determined by the first sensor ( 24 ) and the second sensor ( 25 ).

15. A method for operating a roll assembly ( 10 ) according to claim 1 , comprising pretensioning the first bearing body ( 13 ) and the second bearing body ( 14 ) with respect to one another by the tensioning device ( 16 ) in such a way that the first roll ( 11 ) and the second roll ( 12 ) are pressed towards one another.

16. The method according to claim 15 , further comprising rotating the first abutment body ( 17 ) about a first axis of rotation (A 1 ) in order to set the minimum width of the milling gap.