Society of Motion Picture Engineers : incorporation and by-laws (1927)

780 Transactions of S.M.P.E., Vol XI, No. 32, 1927 The self threading feature is the most novel device on the Model B Kodascope. A reel of film is placed on the upper spindle. The end of the film is inserted in a slot in the upper sprocket clamp and the current turned on, as shown in Fig. 4. The perforations automatically engage the sprocket teeth which send the film into a closed channel, or upper loop former, leading to the pull-down. The pull-down leads the film into another closed channel or lower loop former which leads back to the sprocket. The sprocket sends the film to the take-up reel through another channel which, when in threading position guides the film around the Fig. 4. The Self-Threading Device. take-up reel core. After the film has entered this channel, the current is turned off and, by means of a lever, the loop formers are moved away from contact with the film loops and the current is turned on again, the picture at once showing normally on the screen. When several convolutions of film are wound around the core of the take-up reel, the take-up channel springs apart automatically, the take-up functioning in the ordinary manner. Reverse projection is effected by turning a switch to * 'reverse" position. Normal or reverse projection is accomplished instantaneously. Overrunning clutches in upper and lower reel shafts automatically take care of the reversal. Single frames may be projected at full brilliancy, the film being protected by a special screen between the condenser and the lamp. This shutter is actuated by a lever conveniently placed directly behind the pull-down chamber. Single frames