3848981 is referenced by 4 patents and cites 6 patents.

There is disclosed a motion picture projector with self-threading mechanism. The projector has in the front panel of its enclosure a slot into which is insertable a length of film extending between the two reels of the projector. The self-threading mechanism of the projector comprises a lever or arm which is pivotal from a loading position into a threading position, and vice versa. After dropping a length of film into the slot the lever is pivoted from its loading position into its threading position. While being so pivoted, the lever sequentially causes locking of the film to the take-up sprocket, then to the supply sprocket, then forming the lower loop, then the upper loop, and finally pressing the film into the film channel. The threading mechanism further comprises a control switch arm selectively settable from an OFF position either on forward or on reverse. Setting the control on forward causes wrapping of the film about the capstan of the projector and starts operating of the projector in a conventional manner. Setting of the switch arm on reverse with the pivotal lever in its threading position causes release of the film from the capstan and driving of the film through the projector in reverse direction. The reel constituting the supply reel during forward drive now functions as take-up reel and the reel functioning as take-up reel during forward drive now functions as supply reel. Fast rewind is effected by turning the pivotal lever into its loading position and setting the switch arm on reverse. Placement of the pivotal lever in its loading position releases the film from the sprockets so that the film can now be pulled through the projector at high speed. The mechanism also includes a slip clutch which brakes the reel acting as take-up reel during operation of the projector in the reverse mode and locks the take-up reel against slipping relative to the drive means during fast rewind.

Self-threading motion picture projector
Application Number
Publication Number
Application Date
June 14, 1973
Publication Date
November 19, 1974
Beckman Frank H
Chedister Conkling
Hane Baxley & Spiecens
Kalart Victor Corporation
G03b 01/56
G03B 01/56
G03B 01/00
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