Roller mill drive

In a roller mill drive having two pairs of rolls comprising a first pair of adjacent fast and slow rolls and a second pair of adjacent fast and slow rolls, an improved roller mill drive comprising:

• an endless chain drive connected with both of the fast rolls for rotating the fast rolls in unison;
• a separate serpentine chain drive connected with one of the fast rolls and also connected with both of the slow rolls for rotating the slow rolls in unison at a slower speed than the fast rolls, while obtaining a reversal of rotational direction from the fast roll with which it is connected for rotating each slow roll in a direction opposite to the direction of rotation of its corresponding fast roll;
• and
• drive means for positively driving at least one of said rolls for operating the endless chain drive and the serpentine drive.

A roller mill comprising:

• a first pair of adjacent rolls;
• a second pair of adjacent rolls;
• a first chain drive connected with a roll in said first pair and with a roll in said second pair and operative for rotating both rolls in unison;
• a second chain drive, separate from the first chain drive, connected with one of the rolls with which the first chain drive is connected and also connected with the roll in the first pair and with the roll in the second pair other than the rolls with which the first chain drive is connected, the second chain drive being operative for rotating the rolls with which it is connected in unison;
• and
• drive means for positively rotating at least one of the rolls in the first pair or the second pair for rotating both rolls in each pair through operation of the first and the second chain drives to rotate the first pair of rolls in opposite directions and at a speed differential, while also rotating the second pair of rolls in opposite directions and at a speed differential.

A roller mill comprising:

• a first pair of adjacent fast and slow rolls;
• a second pair of adjacent fast and slow rolls, in which both fast rolls and both slow rolls rotate about their axes on corresponding roll shafts;
• a first chain drive connected directly to the roll shafts of both fast rolls for rotating the fast rolls in unison;
• a separate second chain drive connected directly to the roll shaft of one of the fast rolls and also connected directly to the roll shafts of both of the slow rolls for rotating the slow rolls in unison at a lower speed than the fast rolls, while obtaining a reversal of rotational direction from the fast roll with which it is connected for rotating each slow roll in a direction opposite to the direction of rotation of its corresponding fast roll;
• and
• drive means, separate from the first and second chain drives, directly connected to the roll shaft of at least one of said rolls for operating the first and second chain drives.