the result data generated by the controller the movable jig 130 has two bars crossed at a hinge 133 such that an x axial distance between the two bars is in inverse proportion to a y axial distance between the two bars in one side of the hinge 133 the two bars have stationary ends 135 pivotally fixed to the lift frame 120 and the base frame 110 respectively in the other side of the hinge 133 the two bars have free ends 137 x axially movably connected to the lift frame 120 and the base frame 110 respectively the lift device 140 is preferably comprised of a hydraulic cylinder wherein one end thereof is fixed to the base frame 110 and the other end thereof is connected to the free ends 137 of the movable jig 130 so as to push or pull the free ends 137 thereby varying x and y axial distances to thus move up and down the lift frame 120 and the table 150 supported by the movable jig 130 the back plate section 160 moves the slide back plate 163 that is in support of the weight of the user within an adjustable overall tilt angle of the table 150 slidably up and down in such a way that a plurality of bearings not shown provided on the right left under sides of the slide back plate 163 is inserted into the guide rails 161 provided on the right left sides of.