Patent ID: 8058981

Claim:
A tire pressure-monitoring device (TPMD) having a base cylindrical housing for directly screwing onto an air-pumping inlet-stem on a tire comprising: a tire-pressure engaging-member formed with a central membrane attached onto a base attachment ring wherein said central membrane is formed to directly engage to an air pressure pushing up through said air-pumping inlet-stem from an air filled in said tire wherein said tire-pressure engaging-member is formed as a replaceable single piece to separately place into the base cylindrical housing; an upper cover assembly comprising a receiving cup having a sticking out extension configured to engage the central membrane wherein said receiving cup is engaged to a push down spring surrounded by a press-down ring screwed onto an insulation ring of the upper cover assembly; and said upper cover assembly is formed as a separate piece to screw onto the base cylindrical housing for engaging and pushing down the central membrane onto the air-pumping inlet stem for engaging and detecting a tire pressure of the air filled in said tire.