Three-way valve for an attenuator

A three-way valve for use in a fluid pulsation attenuator type having a flexible diaphragm disposed to move between lower, neutral and upper positions, the diaphragm having one side thereof contacting the fluid having pulsations to be attenuated and the other side disposed to contact the valve, the valve comprising:

• an elongate, hollow casing extending within the attenuator having an air inlet for introducing air thereinto, an air outlet for releasing exhaust from the interior thereof;
• first and second chambers within the casing, spaced apart therein, and in fluid communication with the air inlet and air outlet, respectively;
• a valve head for non-secured, contacting engagement with the diaphragm;
• a bore within the casing, said bore having a soft spring means interposed between the valve head and a plate within the bore on one end of the casing;
• an elongate sliding tube slidably disposed within the casing having one end attached to the valve head and the other end terminating within the casing, said sliding tube including a plurality of orifices in the wall thereof, said orifices disposed between said first and second chambers when the sliding tube is in its neutral position, and movable between the first and second chambers following corresponding movement of the valve head against the diaphragm, said movement of the orifices into the first and second chambers establishing air communication therebetween and the interior of the casing via the sliding tube;
• port means in the casing linking the interior of the casing with the exterior thereof, whereby reciprocal movement of the sliding tube permits selective air communication between the first and second chambers with the interior of the attenuator air tank.