The X-Valve from Parker Hannifin's Pneutronics Div., Hollis, N.H., is an ultraminiature two-way, three-position valve that, despite the small size, handles flows to 10 lpm at 30 psig. The valve's flow rates exceed that of other miniature solenoid valves in its class largely because the coil and body are combined in a single unit with a unique, flow design. Conventional valves have separate coils and bodies.

Energizing the X-Valve shifts a stainless-steel plunger and directs flow. A key feature is that the plunger has Viton elastomeric ends that tightly seal the valve port and greatly simplify internal geometry. This streamlines the flow path and permits close spacing of the pneumatic tubing ports.

Conventional miniature 10-mm valves, on the other hand, require a more-complex construction to seal all ports at only one end of the valve. This causes additional flow restrictions. They also require more components. A typical miniature solenoid valve has as many as 25 internal parts, with the majority requiring critical tolerances that increase manufacturing time and cost. The

8-mm X-Valve has only six parts, which also equates to fewer potential leak paths and higher reliability. Rated life is 25 million cycles.

An additional benefit is that the X-Valve's compact design permits more magnetic material which, in turn, increases actuating force and the ability to seal larger orifices against high pressures. Thus, the X-Valve actuates at higher pressures with higher flow rates versus comparable solenoid valves. Response time is less than 20 msec.

The valve's unitized body is molded of glass-reinforced polybutylene terephthalate (PBT). It features vertical electrical pins on 4-mm centers for metric connector wire termination, or it can be attached to and powered by a printed circuit board. Barbed ports accept 1/16-in. tubing. The valve can also be manifold mounted. Flanges on the valve are assembled with a unique radial seal to eliminate the need for traditional manifold gaskets and their requisite high installation forces.

Compact size and high-flow capabilities make the

X-Valve suited for a variety of industrial, medical, and analytical applications.