In the District Court of the United States, for the Eastern District of Pennsylvania, the United States of America, petitioner, vs. Motion Picture Patents Company, et al., defendants (1914)

13,329 edge 19 and the sliding door 20, which is normally thrown forward by the spring 21, Fig. 2, with sufficient force to clamp the film and hold it from movement. When the 5 door 20 is retracted by pulling on the rod or string 22, which is connected to the arm 22', the film is liberated and allowed to advance. Film-case 2 is provided with a similar door, but the device for moving the 10 door is not illustrated. This arrangement of the sliding door not only holds the film, but it tightly closes the casing, thus excluding light and protecting the sensitive film. The casings or boxes 1 2 are removable, so that 15 they,"with the inclosed film, may be taken bodily from the apparatus. The shaft 6, heretofore referred to, is provided with a detent or stop-wheel 23, the form of Avhich is most clearly shown in Figs. 3 and 4. The 2D wheel 23 is provided with a number of projecting teeth 24, six being shown, which teeth are adapted to strike successively against the face of the cooperating detent or stop-wheel 25 on the shaft 26, which is 25 the armature-shaft of the motor or a shaft which is constantly driven by the motor. The Avheel 25 has a corresponding number of notches 27 at regular intervals around its periphery. These notches are of such size 30 and shape that the teeth 24 can pass .through them, and Avhen the Avheels 23 and 25 are rotated in the direction indicated by the arroAvs each tooth in succession Avill strike the face of Avheel 25, thereby bringing the film 35 absolutely to rest at the same moment that an opening in the shutter exposes the film and will then pass through a notch, allowing the tape-film to be moved forward another step Avhile it is coATered by the shut 40 ter. To aA*oid the danger of the wheel 25 moving so quickly that a tooth cannot enter the proper notch, a laterally-projecting tooth 29 is provided adjacent to each notch. When a tooth 29 strikes a tooth 24, the lat 45 ter tooth Avill be guided by the tooth 29 into the adjacent notch 27. 30 is a detent spring or pawl to prevent backward movement* of the wheel 23. I prefer to so proportion the parts above 50 described that the Avheel 23 is at rest for nine-tenths of the time in order to give to the sensitized film as long an exposure as practicable and is moving forward onetenth uf the time, and said forward movement is 55 made to take place thirty or more times per second, preferably at least as high as fortysix times per second, although the rapidity of movement or number of times per second may be regulated as desired to give satisfac 30 tory results. The longer interATal of rest of the film insures a good impression of the object projected thereon and results in a picture having clean and sharp lines, since the film has sufficient time to become steady and 65 overcome the vibration caused bv the sudden and rapid motions of the feed mechanism. On the shaft 2G or on any suitable shaft driven by the motor is a revolving disk 31, serving as a shutter for alternately exposing and covering the sensitiAre film. This disk, 70 Avhich is continuously revolving, is provided Avith six or any other suitable number of apertures 32 at regular intervals around it near the edge, they being so arranged that one of the apertures passes directly between 75 the camera-lens 33 and the film each time the film is brought to rest, the light-rays passing through the opening 33' and falling on the film half-way between the reels on which the film is wound. 80 34 is a device for adjusting the cameralens toward or from the film, and 35 is a device by means of which the operator can focus the camera on the object to bephotographed. 85 • Although the operation has been partially indicated in the description of the apparatus it av ill now be set forth more in detail. The apparatus is first charged with a sensitive tape film several hundred or even 90 thousands of feet long and the motor is set in operation. Since the spring 21 causes the door 20 to clamp. the film, as already described, the loose pulleys 7 18 slip without pulling said film along, but when. a moving 95 object — for example, a man gesticulating — is placed in the field of the camera and the handle 22 is pulled the film is released and the pulleys operate to pull the same along. At the same time the reel in case 2 is rotated 100 to wind up the film, thus transferring it from the reel in case 1 to the reel in case 2. This movement is intermittent, the film advancing by very rapid steps, which are definitely and positively controlled by means 105 of the peculiar detent or escapement described, and a photograph is taken after each step. While I do not care to limit myself to any particular number of steps per second, there 110 should be at least enough so that the eye of an observer cannot distinguish, or at least cannot clearly and positiA^ely distinguish, at a glance a difference in the position occupied by the object in the successiAre pictures, as 115 illustrated in Fig. 7. A less speed in taking the pictures will cause a trembling or jerky appearance in the reproduced picture. When the movement of the object being photographed has ceased or the desired number of • 123 photographs has been obtained, the apparatus is stopped. The film is suitably treated for developing and fixing the pictures, when positive prints therefrom, Fig. 6, can be used in an exhibiting apparatus. 125 What I claim is — 1. An apparatus for taking photographs suitable for the exhibition of objects in motion, having in combination a camera having a single stationary lens; a single sensi 13*