PURPOSE: To extremely facilitate a jam processing work for a sheet material feeding device by a method wherein a positioning means to position a picture forming device and the sheet material feeding device is rotatably mounted to the sheet material feeding device.

CONSTITUTION: When a sheet material is fed from a sheet feeding device 1 to a laser beam printer 2, the sheet material is fed in the laser beam printer 2 through a sheet feed slot 3a of the laser beam printer 2. When a jam sheet So occurs to the sheet feed slot 3a, the sheet feeding device 1 is rotated around a rotary hinge 9 of a positioning member 6 to separate the sheet feeding device 1 away from the laser printer 2. This constitution accesses the jam sheet So residing at the sheet feed slot 3a without completely removing the sheet feeding device 1 away from the laser beam printer 2, and extremely facilitates a jam processing work.