Moog J814 Series Pneumatic Servo Valves

OVERVIEW

J814 Series Pneumatic Servo Valves are highly responsive and accurate 3-

and 4-way pneumatic servo valves. With excellent reproducibility between

command signal and control pressure, these valves are suitable for pressure

or force control, vibration control, and position control in pneumatic systems.

The 3-way valves can also be used when a vacuum is applied.

The 3-way valves are single stage and available in both standard and high

flow types. The standard type has rated flow of 1 ~ 50 NL/min with valve

pressure drop of 0.5 MPa, while the high flow type has rated flow up to 200

NL/min. The valve is driven by a torque motor which has a pair of nozzles

and a flapper with air gaps. The design is simple and durable for long term

reliability.

The 4-way valves have an orifice in the upper stream of each nozzle, providing

two control ports. These valves are also single-stage, with a rated flow of 1 ~14

NL/min, with a valve pressure drop of 0.5 MPa.

OVERVIEW

Operating principle

• Input current flows through the coils of a torque motor, providing magnetic

power and polarity to the armature.

• Due to the magnetic relationship between the upper and lower poles, the

armature inclines depending on the size of the input current and the polarity

(torque generation).

• The flapper is located between the left and right nozzles and is joined with

the armature. Therefore, a change in the inclination of the ar mature changes

the flapper position, changing the aperture of the left and right nozzles.

• In 3-way valves, the control pressure changes from the supply pressure to

the air pressure according to the aperture of the left and right nozzles.

Therefore, these valves can output control pressure according to the input

current.

• In 4-way valves, two control ports provide output that is roughly

proportional to the input current.

Characteristics

• Single-stage type nozzle flapper valves with torque motors

• High resolution and low hysteresis

• Compact and light

• Low power consumption

• High responsiveness

• Sturdy long-life design free of sliding surfaces