Hy-tec Hydraulics

spring thus move the spool control valve plunger.

As the spool plunger moves inward. The pilot port sleeve is uncovered, the consequent pressure drop allow the regulator ball to sear and pressure is directed to the cylinder to raise the lift arms and implement. As the implement is raised, the compression load on the top link is reduced and by the top link crank (1) will go back and allow the spool control valve (22) to move out by action of feedback spring. The spool cuts off the pilot port and resulting pressure rise unseats the regulator ball to allow pump pressure to return to reservoir. A decrease in implement draft allow the Link outer draft sensing to move back taking the spool control valve with it. This uncover the lowering port, allowing the lift arms and implement to fall until the increase in implement draft moves the control spool through the linkages to close the lowering port.

The draft control lever (14), by moving the rocker draft control (13) of the operating link / link cpte DC actuating move the draft link relative to the DC feedback link outer assy this movement is transmitted to the control spool and oil flows in the appropriate direction until the resulting movement of the lift arms brings the implement draft to the desired setting. The spool then returns to the neutral position to cut off the oil flow.

c.Draft control / sensing element.

1.The Tension or pressure forces acting on the Top link sensing element are converted into control signal i.e.

These signal are taken up by the Top link crank (1) and transmitted to the spool control valve (22) for lifting or lowering action.

2.Operation

In draft control mode, the lever (14) is set at particular position on the quadrant, top link attached to top link crank (1), under