To simply adjust the gap between a moving frame and a fixed frame by rotating the cam integrated with a pin and fitted with the cavity in the upper tubular portion of a hinge connecting the upper and lower tubular portions with the pin.

A moving frame and a fixed frame are fixed to the first and second tubular portions 2, 3 of a hinge, and they are connected rotatably by the hinge. The first and second tubular portions 2, 3 are connected together with the pin of the hinge. First and second adjusting means are provided between both tubular portions 2, 3. The first adjusting means has a cam integrated with the pin 4 and fitted rotatably in a cavity 20. The pin 4 is relatively moved only between both tubular portions 2, 3 by the rotation of the cam 12, thus the gap L between the moving frame and fixed frame is adjusted. The first tubular portion 2 and cam 12 are fixed with a set screw 29 after the adjustment.