Patent GB-599077-A (GB)
Title: Improvements in and relating to photographic cameras
IPC: G03B9/08
Filed: 1944-11-10
Abstract: 599,077. Photographic cameras. STRINGER, H. B. Nov. 10, 1944, No. 22223. [Class 98 (i)] An automatic roll film photographic camera, i.e. one in which the release of shutter, winding of film and rewinding of shutter are all actuated in correct sequence by operation of a single control, is formed in two main units detachable from each other, one comprising the magazine, the other the shutter and lens system, each unit having separate driving means included so that either may be driven independently when the units are separated, and means for operatively inter-relating the functioning of said driving means so that the magazine driving means will operate in correct relationship to the operation of the shutter. As shown in Fig. 1, the camera comprises an upper body portion 5 and a lower portion 2. The upper is provided with a cover 6 secured by a nut 29 and having a light excluding flange 31. The lower body portion 2 has transverse walls 9, 10 supporting a cone 7, through which light for exposure passes, having internal ribs 8 to reduce reflections. A shutter lens assembly 1 is secured to the wall 10 by a spacing member 13. The two parts of the camera are relatively located by a dowel arrangement constituted in part by an electrical connector. The two parts are secured by bolts 22 holding together flanges 20, 21. The upper end of the cone 7 is closed by an optical glass plate 16, adjacent to which are lenses 17 for photographing instruments placed on a panel on the wall 10 for recording on the film details of time and number of an exposure. The plate 16 may be formed used as a correcting lens if desired. The magazine, Figs. 5 and 6, is carried in the upper part of the camera. The film passes from a payout spool 32 over a jockey roller 37, rollers 38, a measuring roller 39 on to the take-up spool 33. The payout spool spindle carries a pulley 41 over which passes a brake band 42 connected at one end to a lever 43 carrying the jockey roller 43, so that the spool is retarded if the film tension slackens. Both spools have quick release devices and guide members 35, 36 to assist their insertion. A film wind indicator is provided in the boss of the securing nut 29 and controlled by a feeder arm 98. A cam driven by the payout spool closes a switch 97 to light a lamp intermittently when the film is feeding normally. A spring urged plate 40 holds the film in contact with the glass plate 16 except when lifted by rotation of the shaft 54. The film is wound by a motor 44, with reduction gearing 45, 46, 47, under control of the device shown in Fig. 7a, of which Figs. 7b, 7c, 7d are sectional views. The gear 47 meshes with a gear 48 secured to a ratchet member 62. The latter is free to revolve on a sleeve 66 carried on a pin 50. To this sleeve is secured a gear wheel 61 carrying pawls 63 on the pivots of which an annular plate 71 is carried on slotted holes so that movement relative to the gear 61 is possible, such movement engaging the pawls 63 with the ratchet 62 by means of pins on the pawls engaging inclined slots 72 in the plate 71, which is urged by the spring 74 in the direction to engage the pawls. The sleeve 66 drives through a pin 70, with lost motion in a slot 70a, a disc 51 having a cam track on its periphery and an annular track 78, with a gap, on its face. The gear wheel 61 has a gap in its teeth but also carries a toothed sector 64 capable of limited movement between stops 68, 68a carried on the gear. When the sector abuts either stop its teeth are in line with those of the gear 61 and the sector always bridges the gap in these teeth. The position of the parts shown is that during exposure. Film winding is initiated by energization of a solenoid 83 which actuates a lever 76 to close a switch 84 and start the motor 44, also to remove abutments 75, 79 from the end of the track 78 and the toe 8 on the plate 71. The follower 52, being near the bottom of the recess on the cam, 51, is pulled to the bottom by the spring 57, the cam being allowed to rotate by the lost motion in the slot 70a. The end of the track 78 thus moves under the abutment 75 and prevents it re-engaging the end of the track when the solenoid is de-energized. The release of the toe 80 allows the pawls 63 to engage the ratchet 62, which is now being driven by the motor 44, to drive the gear 61. The gear 65, which transmits the drive to wind the film is at this time opposite the gap in the teeth of the gear 61 but in mesh with the sector 64. The lost motion in the slot 70a allows the motor 44 to gain speed, after which the cam 51 lifts its follower 52, to rotate the lever 53, and through an abutment 55, a lever 56, secured to the shaft 54 which thus lifts the pressure plate 40. The stop 68a then strikes the sector 64 to dislodge an arm 81 which was retaining it by engagement with a pin 82. The sector 64 and later the gear 61, then drive the gear 65. The abutments 75, 79 arrest the movement after one revolution and the switch 84 is opened to stop the motor. The spring 69 restores the sector 64 to its initial position. The consequent rotation of the gear 65 drives, through gearing 90, 91, 92, the measuring roller 39, which, in one revolution feeds the quantity of film required for one exposure. The roller has a rubber surface. The take-up spool is driven through a slipping clutch 93 and a gear 94 and a free wheel device. An interlock is provided to prevent the pressure plate 40 being raised when the two parts of the camera are separated. The shutter-lens assembly, Fig. 4, comprises upper and lower groups of lens elements 100, 101, with a betweenlens shutter having blades 102. The blades are circular each with a portion removed from its circumference, these portions passing simultaneously between the lens elements for each exposure, the discs 102 making one revolution each. The discs are driven by a toothed annulus 105 engaging pinions 106 on the disc spindles 104. This annulus is driven by a spring motor 109, Figs. 13b, 16, 16a. The spring 108 is secured at one end to a fixed pin 110 and at the other to a drum 11 to which is coupled a ring 113 which has, however, radial movement and is moved by a spring 118 to engage a dog 115 in one of six apertures 116 in a drum 117 attached to the pinion 107 which drives the shutter annulus 105. Just before exposure the dog 115 is engaged in an aperture 116 at A, Fig. 16a, and a detent 131 on an arm 129 engages an aperture at B. The shutter is released by energization of the solenoid 134 which withdraws the detent 131 and allows the spring 108 to turn the drum 111 one-sixth of a turn clockwise. The resulting movement of the pinion 107 produces the exposure. The movement of the drum 111 during exposure is controlled by an air dashpot 120, Fig. 13a, on the piston rod 121 of which is a rack engaging a sector 11a on the drum. Movement of the rod 121 to the right, Fig. 13a, during exposure releases the spring-urged lever 141 of a switch 119, which starts the shutter rewinding motor 122, Fig. 13b, which drives the drum 111 in the direction of the arrows in Fig. 13b, through gearing 123, 124, 127, 128. At the commencement of this movement a cam 133, Fig. 16a, driven off the gear train drives the detent 131 into one of the holes 116 to lock the drum 117 and free the dog 115 which is rotated by the rewinding movement of the drum 111 until it engages the next hole 116. The switch 119 is shown in Fig. 20. The arm 141 is carried on a shaft 140 to which is secured within the casing an arm 139. The latter is connected by a spring 144 to a pivoted cam 142 which rotates anticlockwise when the arm 139 moves to the right. The speed of movement of the cam is controlled by an escapement. Movements of the arm 139 and the cam 142 are restricted by stops 148, 149, 150, 151. The whole sequence of shutter and film winding movements is initiated by energizing the solenoid 134. The release of the shutter moves the arm 139 into the switch 119 to the right allowing the arm 135 to fall to close the contacts 138, 138a to illuminate the instruments to be photographed through the lenses 17. The cam 142 follows with an anticlockwise movement delayed by the escapement which lifts the arm 135 to close the contacts 137, 137a which, through a relay, starts the shutter rewinding motor 122 and the film winding motor 44 and energizes the solenoid 83 controlling the film winding cycle. As the shutter is rewound the piston rod 121 pushes the arm 141 back to the position shown in Fig. 21 when both pairs of contacts are opened. A switch 164, Fig. 13b, is provided which is closed by a cam 165, driven by the shutter annulus 105, to transmit a radar signal at each exposure. According to the Provisional Specification the glass plate 16 may be located by contact with two adjacent sides of the aperture in which it is mounted. Any compensating lens surface formed on it may be spherical or figured. Spirit levels may be built into the flange of the upper unit of the camera.