Power adjusted concave

Claim 2

Threshing apparatus including a rotatable threshing cylinder, a concave mounted beneath the threshing cylinder for movement toward and away from the threshing cylinder to respectively decrease and increase the space between the concave and threshing cylinder, a hydraulic actuator for controlling the concave such that the delivery of hydraulic fluid to the actuator tends to move the concave in one direction relative to the threshing cylinder and the exhaust of hydraulic fluid from the actuator tends to move the concave in the opposite direction relative to the concave, and a movable control valve having Supply, discharge and neutral conditions to respectively establish delivery of hydraulic fluid to the actuator, exhaust hydraulic fluid from the actuator, and block flow of hydraulic fluid to and from the actuator.

Claim 3

Threshing apparatus as claimed in claim 1 wherein the delivery of hydraulic fluid to the actuator tends to move the concave toward the threshing cylinder to decrease the space between the concave and threshing cylinder, and further including relief valve means between said hydraulic actuator and said valve operable in response to excessive loads between the concave and threshing cylinder to connect the actuator with sump.

Claim 4

Threshing apparatus as claimed in claim 2 further including a signal, and means responsive to flow through said relief valve means for actuating said signal.

Claim 5

Threshing apparatus as claimed in claim 2 further including followup means interconnected between the concave and the control valve for actuating the control valve from its neutral to discharge condition in response to excessive loads between the concave and threshing cylinder, and thereafter to cause the control valve to return to the neutral position when the excessive loads are relieved.

Claim 6

Threshing apparatus as claimed in claim 1 further including a concave position selector lever connected with said control valve operable to actuate the control valve to move the concave to a selected operating position relative to the threshing cylinder, and followup means interconnected between the control valve and concave operable to move the control valve to its neutral position as the concave assumes said selected position.

Claim 7

Threshing apparatus as claimed in claim 1 further including an operating arm on the control valve, a floating lever pivotally mounted intermediate its ends on said operating arm, followup means connected with one end of said floating lever, said followup means being movable in opposite directions in response to movement of the concave in opposite directions, and concave position selector means connected with the other end of said floating lever for positioning said other end in accordance with a selected position of the concave relative to the threshing cylinder. 7 Threshing apparatus including a threshing drum; a concave mounted adjacent the threshing drum for movement toward and away from the threshing drum to respectively decrease and increase the space between the concave and threshing drum; power means for controlling the position of the concave relative to the threshing drum; and movable control means for said power means having a first position to condition the power means in a direction to effect movement of the concave toward the threshing drum, a second position to condition the power means to maintain the concave in a fixed position relative to the threshing drum, and a third position to condition the power means in a direction to effect movement of the concave away from the threshing drum.

Claim 8

Threshing apparatus as claimed in claim 7 further including means responsive to a predetermined increase in the load between the concave and threshing drum to allow movement of the concave upon said predetermined increase in load when said control means is in said second position.

Claim 9

Threshing apparatus including a rotatable threshing cylinder, a concave mounted beneath the threshing cylinder for movement toward and away from the threshing cylinder to respectively decrease and increase the space between the concave and threshing cylinder; an actuator for controlling the concave including a hydraulic cylinder, a piston reciprocable in the hydraulic cylinder and having a rod projecting from one end of the hydraulic cylinder; linkage means connecting the piston rod with the concave so that the concave moves away from the threshing cylinder as the piston rod projects from the hydraulic cylinder and moves toward the threshing cylinder as the piston rod retracts within the hydraulic cylinder; a pump; a first line connecting the pump output with the end of the hydraulic cylinder through which the piston rod projects; a second line connected with the end of the hydraulic cylinder opposite the piston rod; and a movable control valve having a supply position in which said second line is connected with the pump output, a neutral position in which fluid is trapped in said second line, and a discharge position in which said second line is connected with a sump.

Claim 10

Threshing apparatus including a rotatable threshing cylinder, a concave mounted beneath the threshing cylinder for movement toward and away from the threshing cylinder to respectively decrease and increase the space between the concave and threshing cylinder; an actuator for controlling the concave including a hydraulic cylinder, a piston reciprocable in the hydraulic cylinder and having a rod projecting from one end of the hydraulic cylinder; linkage means connecting the piston rod with the concave so that the concave moves away from the threshing cylinder as the piston rod projects from the hydraulic cylinder and moves toward the threshing cylinder as the piston rod retracts within the hydraulic cylinder; a pump; a first line connecting the pump output with the end of the hydraulic cylinder through which the piston rod projects; a second line connected with the end of the hydraulic cylinder opposite the piston rod; and a movable control valve having a supply position in which said second line is connected with the pump output, a neutral position in which fluid is trapped in said second line, and a discharge position in which said second line is connected with a sump.

Claim 11

Threshing apparatus as claimed in claim 9 further including a relief valve operable in response to increases beyond a predetermined maximum pressure in said first line to connect said first line with sump until the pressure falls below said predetermined maximum.

Claim 12

Threshing apparatus as claimed in claim 10 further including means for actuating said control valve to its supply or discharge positions to effect movement of the concave to a selected position relative to the threshing cylinder, said means causing said control valve to assume its neutral position as the concave assumes said selected position.

Claim 13

Threshing apparatus as claimed in claim 11 wherein said means includes followup mechanism operable to actuate said control valve in a direction to effect return movement of the concave to said selected position subsequent to movement of said concave away from selected position due to overload.