Means for preventing film movement in a camera

Claim 2

In a still camera having (1) a housing including spaced takeup and supply compartments for receiving respectively take-up and supply rolls of film perforated at predetermined metering intervals, (2) means defining an exposure plane between said compartments, (3) transport means for advancing received film along said exposure plane from said supply compartment to said take-up compartment, (4) a metering mechanism having an active condition disabling said transport means and an inactive condition, (5) a film sensing pawl mounted on said housing for movement from a retracted position on one side of said exposure plane to a locking position transversing said exposure plane when intercepting one of said perforations, and (6) means, interconnecting said metering mechanism and said film sensing pawl, for placing said metering mechanism in its active condition when said sensing pawl is moved to its locking position; the improvement comprising a second pawl mounted in said housing on one side of and transversing said exposure plane, said second pawl being positioned to enter a film perforation when said sensing pawl moves to its locking position for preventing film movement along said exposure plane.

Claim 3

The improvement as defined in claim 1 wherein said second pawl has a bevelled edge transversing said exposure plane and facing generally toward said supply compartment, whereby the trailing edge of a preforation through which said second pawl extends may cam over said second pawl as the film is advanced.

Claim 4

The improvement as defined in claim 1 wherein said sensing pawl and said second pawl are coaligned in a direction transverse to the direction of film advance, whereby both pawls are in the same film perforation when said sensing pawl is in its predetermined extended position.

Claim 5

In a still camera having (1) a housing defining a space for receiving roll film perforated at predetermined metering intervals, (2) means defining an exposure plane, (3) transport means operable for advancing received film along said exposure plane, (4) a film sensing pawl movable between a retracted position on one side of said exposure plane and a predetermined extended position transversing said exposure plane through one of the film perforations to detect the presence of a perforation at a predetermined position, (5) metering means interconnecting said sensing pawl and said transport means for disabling said transport means when said sensing pawl detects the presence of a perforation at said predetermined position, and (6) means interconnecting said transport means and said sensing pawl for returning said sensing pawl to its retracted position except during operation of said transport means; the improvement comprising a second pawl fixed in said housing on one side of and transversing said exposure plane, said second pAwl being positioned to enter a film perforation when said sensing pawl detects the presence of a perforation at said predetermined position for preventing film movement along said exposure plane.

Claim 6

In a still camera having (1) a housing defining a space for receiving roll film perforated at predetermined metering intervals, (2) means defining an exposure plane, (3) transport means operable for advancing received film along said exposure plane, (4) a film sensing pawl movable between a retracted position on one side of said exposure plane and a predetermined extended position transversing said exposure plane through one of the film perforations to detect the presence of a perforation at a predetermined position, (5) metering means interconnecting said sensing pawl and said transport means for disabling said transport means when said sensing pawl detects the presence of a perforation at said predetermined position, and (6) means interconnecting said transport means and said sensing pawl for returning said sensing pawl to its retracted position except during operation of said transport means; the improvement comprising a second pawl fixed in said housing on one side of and transversing said exposure plane, said second pAwl being positioned to enter a film perforation when said sensing pawl detects the presence of a perforation at said predetermined position for preventing film movement along said exposure plane.

Claim 7

The improvement as defined in claim 4 wherein said sensing pawl has a bevelled edge transversing said exposure plane and facing in a direction generally opposed to the direction of film transport, whereby the trailing edge of a perforation may cam over said second pawl as the film is advanced.

Claim 8

The improvement as defined in claim 1 wherein said second pawl is adjacent to said sensing pawl in a direction transverse to the direction of film advance, whereby both pawls enter a film perforation at said predetermined position.