Adjustable Air Supply Valve Of Air Cushion Bed

An adjustable air supply valve of an air cushion bed is disclosed, the air supply valve has an air supply valve installed between a first tube and a second tube. The air supply valve comprises a round seat, an air valve, a cover plate, a locking plate and a driving element. It has the operation modes of full opening for supplying air, half opening for supplying air, full closing and venting. Therefore, it can be operated to met the requied condition. Especially, if the air cushion bed is designed to have a plurality of different sections which can be adjusted based on different parts of the human body. The adjustable air supply valve has the effect of independently supplying air to the different sections. An adjustable air supply valve of an air cushion bed having an air supply valve installed between a first tube and a second tube; the air supply valve comprising a round seat, an air valve, a cover plate, a locking plate and a driving element, wherein the round seat is clamped between the first tube and the second tube; the round seat is a hollow cylinder with a plate in the middle section within the cylinder for assembling the air valve; a first notch is formed at a lateral side of the round seat; a first lock hole and a second lock hole are formed at a periphery of the round seat; the air valve has a size slightly smaller than the round seat and is rotationably installed to the round seat; a lateral side of the air valve has three cambered plates; three notches are formed between the plates; at a side opposite the cambered plates are installed with a protruding ring; a monitoring notch is formed on the protruding ring; a plurality of posts are installed at inner sides of the cambered plates; each post has a third lock hole; the cover plate serves to cover the air valve and has a shape approximately corresponding to that of the air valve; the cover plate has through holes at positions corresponding to the posts; a center of the cover plate is installed with a central hole; a plurality of screws are used to lock the through holes to the third lock holes; thereby, the cover plate is locked to the air valve; the locking plate has an aperture at a center thereof; a fourth lock hole is formed on a periphery of the locking plate; a second screw serves to lock the locking plate to the first lock hole; and a driving element is a step motor and a periphery thereof has a plurality of fifth lock holes; the driving element is locked to the second lock hole by screwing screws to the fifth lock holes; a driving block is formed on a center of the driving element; a shape of the driving block is exactly identical to the central hole; in assembly, the air valve is exactly received in the round seat; the protruding ring is embedded in the annular trench; the cover plate, locking plate and driving element are sequentially placed upon the air valve; the driving block is exactly buckled in the central hole; the round seat is locked with the locking plate and driving element; thereby, the air valve and cover plate are combined, by the driving block of the driving element to drive the central hole; the air valve is rotatable in the round seat. 2. The adjustable air supply valve of an air cushion bed as claimed in claim 1, wherein an outer side of the round seat is added with a sensor; wherein by a hole on the annular trench, the sensor senses the rotation position of the air valve; and an annular trench is formed on the plate.