PURPOSE: To reduce the number of parts and to extend a space for mounting by providing a film pressing plate holding each of a magnetic head, a pressing member and a signal generator and giving the function as an inside cover to the pressing plate.

CONSTITUTION: The magnetic head 2 is fixed on the pressing plate 1 so that a film contact surface 2a is flush with the film contact surface 1b of the pressing plate 1. Since the pressing plate 1 is in contact with the outside rail 7a of a camera main body 7, a film 11 passes inside a tunnel formed between the inside rail 7b of the camera main body 7 and the pressing plate 1 from a gate part composed of the part 1d of the pressing plate 1 and the part 7b of the camera main body 7. Then, a photosensor 3 projects light onto the perforation passing position of the film 11, to detect the presence of the light reflected from the film 11, generates a pulse signal used for controlling the position of the film 11 and is stuck/fixed on the pressing plate 1.