Roll center for attachment frame control arms

A harvesting header for an agricultural harvesting machine, the header comprising:

• a first frame portion;
• a second frame portion moveably connected to the first frame portion;
• an upper control arm connected to the first frame portion at a first contact point and connected to the second frame portion at a second contact point;
• and
• a lower control arm connected to the first frame portion at a third contact point and connected to the second frame portion at a fourth contact point,
• wherein, when the harvesting header is attached to a harvesting machine, an upper control arm axis is defined by a line passing through a first planar representation of the first contact point and the second contact point and a lower control arm axis is defined by a line passing through a second planar representation of the third contact point and the fourth contact point, and wherein a roll center is defined by the intersection between the upper control arm axis and the lower control arm axis, and wherein the roll center is positioned at or below ground level over which the machine is configured to travel and positioned behind the second frame portion relative to a direction of travel, and wherein the first planar representation and the second planar representation are coincident planes orthogonal to the ground level and extending along the chassis axis.

An agricultural harvesting machine comprising:

• a chassis;
• ground engaging members for moving the chassis;
• a feederhouse connected to the chassis for receiving agricultural material;
• a harvesting header for cutting and gathering agricultural material and delivering it to the feederhouse, the harvesting header including;
• a first frame portion;
• a second frame portion moveably connected to the first frame portion;
• an upper control arm pivotally connected to the first frame portion and pivotally connected to the second frame portion;
• and
• a lower control arm pivotally connected to the first frame portion and pivotally connected to the second frame portion,
• wherein, when the harvesting header is attached to a harvesting machine, the connection between the first frame portion, second frame portion, upper control arm, and a lower control arm forms a roll center positioned at or below ground level over which the machine is configured to travel and behind the second frame portion relative to a direction of travel.