A technical layout is presented in this invention which can continuously and conveniently change the angles of the inclination of the supporting legs in a supporting device with oblique supporting legs having constant length. The basic thinking about the device is as follows: the axes used in this device are divided into fixed axes and moving axes. Each moving axis is formed by the combination of an axis, a slider and at least a locking device and in a complete supporting device at least two moving axes are included. Three kinds of adjusting devices of hooping type, sliding type and rope-adjustable type are designed to move the moving axes conveniently. In the device of hooping type, the axis ocnnecting two supporting poles function as moving axis, while in the devices of sliding type and rope-adjustable type, the axes connecting the supporting legs or jackstays function as moving axes. |