Pneumatic diaphragm piece

The invention discloses a pneumatic diaphragm piece. The pneumatic diaphragm piece comprises a disc-shaped diaphragm piece body. An annular groove is formed in the annular inner side face of the diaphragm piece body. A plurality of concentric round wrinkle-preventing reinforcement ribs are arranged in the annular groove. Each wrinkle-preventing reinforcement rib circle is composed of a plurality of arc-shaped wrinkle-preventing rib segments distributed at intervals. The pneumatic diaphragm piece is simple in structure and reasonable in design; the wrinkle-preventing reinforcement ribs are arranged in the arc-shaped groove, and divided into the small arc-shaped rib segments, so that the diaphragm piece body is softer, tensile strength and strength are improved, wrinkles are avoided, and the use needs of enterprises are met.