PURPOSE: To obtain a detachable safety frame by dividing the frame into a front, an upper and a rear frame to be freely jointed, thereby fixing the front frame on the body of a machine, jointing the upper frame with the rear frame, mounting the jointed frame to the rear end of the machine body, and then turning it to the front for jointing with the front frame.

CONSTITUTION: After a front frame 2 is firmly fixed via fixing plate 2a, a safety frame 1 composed of an upper frame 3 and a rear frame 4 firmly jointed is supinely laid behind the body of a machine. Then, a tractor A is driven back, and a supporting pin 6 firmly planted on the lower part of the rear end of the tractor is fitted to a metal connector 4b fixed on the rear frame 4. A lift arm 7 is connected with a connecting pin 4d on one side firmly planted on the rear frame 4 through a lift rod 9, and shaked and lifted upward. Subsequently, a lift arm 8 is connected with a connecting pin 4e through a lift rod 10. After the lift rod 9 is removed, the safety frame 1 is slowly turned to the front, and connected with the front frame at its top.