Rotor reversing mechanism

1. A reversing mechanism for a rotor of a baler or of an in-feed system, comprising

a ratchet mounted for rotation with the rotor,

a pawl carried by a reversing arm for engaging the ratchet,

a double acting hydraulic cylinder for reciprocating the reversing arm to cause the rotor to rotate in a reverse direction; and

means for disengaging the pawl from the ratchet when the reversing arm is in a park position; and

a park spring for urging the reversing arm towards the park position and working chambers of the double acting hydraulic cylinder are permanently in fluid communication to one another by way of a throttled passage.

2. A reversing mechanism as claimed in claim 1 , wherein the hydraulic cylinder has a differential piston and the pressure acting on the larger face of the piston acts to move the reversing arm towards the park position.

3. A reversing mechanism as claimed in claim 1 , wherein the reversing arm is mounted for rotation about the axis of the rotor and the pawl is pivotably mounted on the reversing arm in such a manner as to engage with the ratchet teeth under the action of a further spring, the pawl being pivoted against the action of the spring when it comes into a contact with a stationary abutment in the park position of the reversing arm.

4. A reversing mechanism as claimed in claim 1 , wherein the park spring urging the reversing arm towards the park position acts on the reversing arm by way of a lever system configured to increase the spring force acting on the reversing arm as it approaches the park position.

5. A reversing mechanism as claimed in claim 4 , wherein the lever system comprises a first lever rotatable at one end about an axis that is fixed in relation to the rotor axis and carrying at its opposite end a two-armed lever, one arm of the two-armed lever being connected to the reversing arm and the other to the park spring urging the reversing arm towards the park position, the opposite end of the latter spring being anchored to a point that is fixed relative to the axis of the rotor.

6. A reversing mechanism as claimed in claim 5 , wherein the two-armed lever is a bell crank lever and the anchoring point of the park spring coincides with the pivot axis of the first lever.

7. A reversing mechanism for a rotor of a baler or of an in-feed system, comprising

a ratchet mounted for rotation with the rotor;

a pawl carried by a reversing arm for engaging the ratchet;

a double acting hydraulic cylinder for reciprocating the reversing arm to cause the rotor to rotate in a reverse direction;

means for disengaging the pawl from the ratchet when the reversing arm is in a park position; and

a park spring for urging the reversing arm towards the park position and working chambers of the double acting hydraulic cylinder are permanently connected to one another by way of a throttled passage;

the park spring urging the reversing arm towards the park position acts on the reversing arm by way of a lever system designed to increase the spring force acting on the reversing arm as it approaches the park position; and

the lever system comprising a first lever rotatable at one end about an axis that is fixed in relation to the rotor axis and carrying at its opposite end a two-armed lever, one arm of the two-armed lever being connected to the reversing arm and the other to the park spring urging the reversing arm towards the park position, the opposite end of the latter spring being anchored to a point that is fixed relative to the axis of the rotor.

8. A reversing mechanism as claimed in claim 5 , wherein the two-armed lever is a bell crank lever and the anchoring point of the park spring coincides with the pivot axis of the first lever.