This invention relates to an arrangement for coupling undeveloped films to a leader.
When developing undeveloped films (hereinafter simply referred to as "films") in an automatic film developing machine of a type that utilizes leaders to guide films, the front ends of films F are connected to a leader L after pulling them out of patrones P as shown in FIG. 27. The films F are sent to the film developing unit, led by the leader.
The leader L is formed of a flexible synthetic resin sheet. Along its longitudinal center are formed a plurality of holes a arranged at equal intervals and adapted to engage a feed sprocket provided in the film developing unit.
Such an automatic film developing machine is ordinarily provided with a film guide. If films are detached from the film guide while being fed, their surfaces may be damaged due to contact with the film guide. Thus, it is necessary to couple films reliably to the leader with high positional accuracy.
If a film F should come off the leader L while developing, it will be stuck in the treating solution. It is extremely troublesome to take out such a stuck film. If taken out carelessly, the film F may be exposed to light. Thus, films F have to be rigidly coupled to leaders L.
For this purpose, films F were heretofore connected to a leader F by means of splicing tapes T as shown in FIG. 27.
In order to connect films to a leader using splicing tapes T with high positional accuracy, the leader has to be placed on a special-purpose workbench. It is necessary to keep oil and dust from the adhesive surface of the splicing tapes T. Thus, a taping job tends to be very troublesome. In order to prevent films F from coming off the leader while being fed, it is necessary to use splicing tapes with high bond strength. It is difficult to peel off such tapes after developing films F. Such tapes are not recyclable and thus are uneconomical.