Film sensing apparatus
AssigneeAMF Incorporated
InventorArthur Stanford
Life of this patent
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Abstract
As film is being drawn off a rotatable supply reel, an apparatus indicates the presence of a predefined amount of film material remaining on the reel. In the absence of a designated quantity present on the film reel, a sensing device in proximity to the reel imparts a signal to a reel braking device for de-energizing the film roller. When the braking device moves to engage the film reel, an additional sensing device responds to the angular displacement between the brake and the film reel during braking action to monitor film tension.
Claims2
A film sensing apparatus for indicating the presence of a predefined amount of film remaining on a film supply reel, said reel being adapted to continuously dispense film from a freely moving film roll spindle for controlled movement of said spindle supported at each end upwardly and downwardly, including:
- supply sensing means disposed in proximity to said reel, responsive to a predefined quantity of film on said reel, said supply sensing means being defined by a sensing arm in contact with said film roll responsive to upward and downward movement of said spindle;
- brake means for engaging said film roll spindle in the absence of a designated film tension;
- and film tension sensing means disposed in proximity to said film being drawn from said film supply reel for governing movement between said brake means and said film spindle, said film tension sensing means moving angularly with respect to said film being drawn from said film supply reel in response to the tension of the film, said brake means movement in an upward direction being responsive to movement of said film tension sensing means in a downward direction, causing said film spindle to de-accelerate responsive to decreased tension and said tension sensing means to reverse its angular movement to urge said brake downward for disengagement from said spindle, permitting said spindle to travel upwardly and downwardly in an oscillatory manner.
Dependencies are inferred from the claim text.