Round baler binding arrangement including twine tension control

In a binding arrangement for applying binding material to the circumference of a large round bale, and including at least one binding material delivery arm mounted for movement for selectively sweeping a delivery end of said delivery arm back and forth, during each binding cycle, between starting and ending positions spaced from each other along a transverse delivery path forward of said bale, at least one cutting arrangement, for severing a length of wrapping material at a location between said ending position and a bound bale, at least one brake including cooperating braking surfaces for contacting the binding material, and a brake control arrangement for selectively effecting a variance in the amount of force exerted by said braking surfaces on said binding material, the improvement comprising:

• said brake control arrangement including control components operating as a function of the position of said delivery end of said delivery arm is during a binding cycle so as to effect at least two changes in braking force within each binding cycle said at least one brake includes first and second brake bodies that are respectively provided with said braking surfaces located opposite each other at a controllable distance;
• said first brake body being controlled and configured as a brake plate;
• said second brake body being fixed and provided with parallel guide bores;
• parallel guide pins respectively extending through said guide bores;
• said first brake body being fixed to lower ends of said guide pins;
• a control plate being fixed to upper ends of said guide pins;
• and said biasing arrangement acting on said second brake body so as to effect said pre-selected braking force between said first and second brake bodies;
• a biasing arrangement acting on said first brake body for urging the latter toward said second brake body so as to effect a pre-selected braking force;
• said brake control arrangement including first and second control elements coupled for movement with said at least one binding material delivery arm and associated with said at least one brake for sequentially effecting movement of said first brake body away from said second brake body in opposition to said biasing arrangement for causing a braking force less than said preselected braking force.

A method of controlling the tension in a binding material being delivered by a binding arrangement including at least one binding material delivery arm mounted for movement during a binding cycle, so as to move a delivery end of the arm along a transverse path between starting and ending positions forward of a zone to be occupied by a circumference of a cylindrical bale, at least one cutting arrangement located between said ending position and said zone for severing the binding material so as separate it from a bound bale, and at least a first brake provided for engagement with said binding material, said method comprising:

• (a) establishing a pre-selected maximum braking force in said first brake;
• (b) controlling said first brake such that it effects a variable braking force such that:
• (i) a decrease in braking force occurs at the beginning of a binding cycle;
• (ii) increasing the braking force back to said maximum braking force until an end of the binding cycle is imminent;
• (iii) and once again decreasing the braking force approximately at the time that the binding material is being severed by the cutting arrangement.