<p>A discharge valve for a refrigerant compressor includes a leaf spring 10 for biasing a flexible valve plate 9 which opens and closes a refrigerant discharge port 8. The leaf spring has a centrally deformed portion which engages an intermediate portion of the valve plate. During the initial opening of the discharge port, no spring force is applied to the free end 9a of the valve plate to thereby reduce any opening delay and increase the efficiency of the compressor.</p>
