Abstract: A directional valve for controlling an actuator by a pressurized medium, including: a pressure port; a work port; a tank port; a spool moving axially inside the directional valve; a first position of the spool, in which the spool tends to be set, and a second position, to which the spool can be moved by a pilot control force and in which the spool opens the flow of pressurized medium from the pressure port to the work port. The directional valve further includes a feedback chamber in which the pressure generates a feedback force effective on the spool and opposite to the pilot control force. In its second position, the spool guides the pressure of the work port to the feedback chamber, and in the second position, the directional valve generates a feedback force proportional to the pressure of the work port, moving the spool to shut off the flow.

Abstract: A directional valve for controlling an actuator by means of pressurized medium, including: a spool fitted to move axially inside the directional valve; a first position of the spool, in which the spool tends to be set; and a second position of the spool, to which the spool can be moved by a pilot control force. Additionally, the directional valve includes a metering orifice placed in the pressure port or in the first work port or in the second work port or in the tank port, and across which a pressure difference is effective. The spool further includes a second position, to which the spool can be moved by a pilot control force. When the spool is in at least the second position, the directional valve is fitted to generate a compensating force proportional to said pressure difference, to move the spool to compensate for the flow.

Abstract: A directional valve for controlling an actuator by a pressurized medium, including: a pressure port; a work port; a tank port; a spool moving axially inside the directional valve; a first position of the spool, in which the spool tends to be set, and a second position, to which the spool can be moved by a pilot control force and in which the spool opens the flow of pressurized medium from the pressure port to the work port. The directional valve further includes a feedback chamber in which the pressure generates a feedback force effective on the spool and opposite to the pilot control force. In its second position, the spool guides the pressure of the work port to the feedback chamber, and in the second position, the directional valve generates a feedback force proportional to the pressure of the work port, moving the spool to shut off the flow.

Abstract: A directional valve for controlling an actuator by means of pressurized medium, including: a spool fitted to move axially inside the directional valve; a first position of the spool, in which the spool tends to be set; and a second position of the spool, to which the spool can be moved by a pilot control force. Additionally, the directional valve includes a metering orifice placed in the pressure port or in the first work port or in the second work port or in the tank port, and across which a pressure difference is effective. The spool further includes a second position, to which the spool can be moved by a pilot control force. When the spool is in at least the second position, the directional valve is fitted to generate a compensating force proportional to said pressure difference, to move the spool to compensate for the flow.