Film advance mechanism

DETAILED DESCRIPTION Having described the invention, what is claimed as new and secured by Letters Patent is: 1.
In a photographic camera of the self-developing type for use with, and adapted to seatingly receive, a film assemblage having a casing that contains at least one self-developing film unit, said film unit having a photosensitive surface and being disposed within said casing with said surface located for photographic exposure through a casing exposure opening, the casing further having (i) a frontal film unit exit passage, (ii) a wall portion extending between a frontal location and a back location and contiguous with said exposure aperture.
and (iii) an access opening in said wall portion in communication with said exposure aperture and extending for a limited selected length in a front to back direction, said access opening being located for providing access from outside said casing to engage said one film unit therein and advance it out of said casing in a back to front direction through the casing exit opening, improved film advance means comprising A.
slide means mounted on the camera for movement relative thereto along the back to front direction between first and second positions, and B film-engaging means mounted for movement by said slide means for engagement of said one film unit through the casing access opening for advancing the film unit in the back to front direction to project out of the casing exit opening, and for further engagement with such film unit other than through the access opening for continued further advance of the film unit further out of the casing, thereby to advance the film unit in the back to front direction by a distance by a distance greater than the length of said access opening.
2.
In a camera as defined in claim 1, the further improvement comprising means for restricting said slide means from undergoing movement in a direction opposite to that which advances the film unit, during engagement of the film-engaging means with film unit being advanced in the camera