Abstract: A feeding device includes a paper feed tray, a detector on an image forming apparatus main body, a control member rotatably supported by the paper feed tray, and spacers. The detector includes movable pieces and contact points corresponding to the movable piece, and switches each contact point by the position of the corresponding movable piece. The control member includes a control surface formed on its outer circumferential surface with projecting and recessed portions. The projecting and recessed portions are disposed in a pattern corresponding to rotation angles in an area of the control surface facing the movable pieces. Controlling the positions of the movable pieces according to the pattern encodes paper size. Each movable piece is lined in the circumferential direction facing the control surface. The outer circumferential surface of the projecting portions is formed in a cylindrical surface shape centering around the rotational axis of the control member.

Abstract: A sheet supplying device includes a recording media container to accommodate a stack of recording media therein, a sheet feeding unit to feed a recording medium from the stack of recording media in the recording media container, a frame to support the recording media container and the sheet feeding unit, a holder to hold the recording media container by surrounding the outer circumference of the recording media container, and a locking mechanism to engage the frame and the holder with each other. The recording media container is detachably attachable to the frame in a first detaching and attaching operation and a second detaching and attaching operation. The locking mechanism causes the frame and the holder to engage at removal of the recording media container in the first detaching and attaching operation.

Abstract: A disc brake for service combined with parking operation is provided which includes a cylinder component, a shaft to be braked, a stator impossible to rotate relative to the cylinder component but possible to move axially relative to the shaft, a friction disc impossible to rotate relative to the shaft but possible to move axially relative to the shaft, a piston slidably engaged to the cylinder component and allowing the stator to frictionally engage the friction disc by a fluid pressure, a plate located at an end of the piston on the side opposed to the side facing the stator and the friction disc, the plate being rotatable by an exterior force, and a ball ramp mechanism provided between the piston and the plate.