Patent GB-678504-A (GB)
Title: Improvements in or relating to photographic cameras
IPC: G03B17/53
Filed: 1948-07-08
Abstract: 678,504. Automatic photographic cameras. EASTMAN KODAK CO. July 8, 1948 [Dec. 13, 1947], No. 18435/48. Class 98 (i). A camera of the type in which manual actuation of a single member effects the sequential actuation of a shutter for exposing a frame of a strip film and means driven by an electric motor for advancing an unexposed frame of film into the exposure gate, includes a single-cycle electric circuit completed by manually operable means for effecting a single shutter operation and film feed cycle, and a multiple-cycle electric circuit which is connected in parallel with the singlecycle electric circuit for a predetermined period upon actuation of switch means to initiate a predetermined number of cycles of shutter operation and film feeding. The switch means may include an actuating member disposed in the path of movement of a cover for the film supply chamber and operable by closing movement of the cover, and preferably includes an actuating member disposed in the film path and operable by the trailing edge of the film. Means may also be provided for cutting the film at the end of each film frame, either automatically as part of the cycle of exposure and film feeding or under the control of a manually-operable switch means. As shown, an electric motor 31 when energized by closing the camera film chamber 10 rotates through a worm drive 33, 34 a shaft 32 which drives shafts 24, 40, 43, 45 through free-wheel type clutches 49 having members 50 driven by driving members 53 on release by solenoids 61 ... 64, of pivoted detents engaging noses on the driven members 50, the driving clutch members for shafts 24, 40, 43, 45 being rotated from the shaft 32 by belt and pulley or like drive 46 ... 48 ; gears 35, 36, 38, 39 ; gears 41, 42 ; and gears 41, 44 respectively. In each clutch the driving member 53 is freely mounted on the driven shaft to which is keyed the driven member, and a disc 56 freely mounted on the shaft carries pins 57 which extend into wedge-shaped recesses in the members 50, into engagement with which the pins are spring-urged, a pin 59 on the driven members 50 being engaged by a pivoted link preventing backlash when the member 50 is arrested by the solenoid-controlled pivoted detents. Shaft 43 carries cams 68 ... 71 effecting respectively feeding of the film F, actuation of the shutter 14 and operation of a flashlight synchronizer 102, operation of a knife 79 to cut off the exposed film, and means for operating the clutch on shaft 43 to permit only a single revolution thereof in the absence of a further pulse from a circuit operated by a switch 77 closed by a cam 76 on the shaft 40, one revolution of which, due to the gear ratio between the respective drives, rotates the shaft 43 sixteen times by successive actuations of solenoid 63. The film F is fed by pairs of rollers 19, 21 and 17, 18, roller 19 which measures the film feed being rubber-covered and secured to the shaft 24 and belt-connected to the roller 18. Instead of a single roller 19, a pair of rubber-covered wheels engaging the film margins may be used. The cams 68 ... 71 and 76 operate normally open single throw switches 72 ... 74 and double-throw switches 75, 77. With no film in the camera, the film chamber cover 11 and main switch 104 open, and the receiving magazine 30 removed, the electrical circuits are in the position shown in Fig. 15, and the cams 68 ... 71 and 76 are as in Figs. 10-14. A roll of film is then placed in the chamber 10, the leading edge is inserted between the rollers 17, 18, and the magazine 30 is placed in the camera closing switch 90, closure of the main switch lighting a white indicating lamp 107, and a red pilot lamp 132. As the cover 11 is closed, switch 92 is closed to energize a relay Y which closes contacts Y<SP>1</SP>, Y<SP>2</SP> and opens contact Y<SP>3</SP>. Closing of Y<SP>1</SP> energizes solenoid 62, switch 77<SP>11</SP> being normally closed, to release shaft 40. Closing of switch 91 by the cover 11 then energizes solenoid 63 through contact Y<SP>2</SP>, thereby releasing shaft 43, and also energizes relay X which closes switches X<SP>1</SP> to light an amber lamp 123, and X<SP>2</SP> to start the motor 31. Shaft 40 then rotates, cam 76 opening switch 77<SP>11</SP> and de-energizing solenoid 62, so that shaft 40 can make only one revolution, and closing a hold-on switch 77<SP>1</SP> for the relay Y, switch 92 then re-opening as the cover 11 no longer actuates it. Simultaneously with the closing of switch 77<SP>1</SP> by cam 76, cam 71 on shaft 43 closes switch 75<SP>1</SP> and opens switch 75<SP>11</SP>, closing for one revolution of shaft 43 a hold-on circuit for relay X and de-energizing solenoid 63 so that shaft 43 will make only one revolution. As the shaft 43 continues to rotate, the shutter 14 is tripped through linkage 83 by a projection 81 on the cam 69 which also closes switch 73 in the flashlamp synchronizer circuit, the synchronizer 102 not being energized, however, since switch Y<SP>3</SP> is open. Next cam 68 closes switch 72 energizing solenoid 61, whereby an exposure frame of film is fed into the exposure gate, in turn operating switches 95, 98, opening 95<SP>1</SP>, 98<SP>1</SP> and closing 95<SP>11</SP>, 98<SP>11</SP>, the last-named switch de-energizing red lamp 132. Thereafter cam 70 closes switch 74 to energize solenoid 64 and effect rotation of shaft 45 so that the cam 78 operates the knife 79 to cut the film against the action of a return spring 80, the cut-off area falling into the light-tight cassette 30. This cycle of exposure, film feed and cutting off of the exposed area is repeated 16 times before the cam 76 on shaft 40 allows switch 77<SP>1</SP> to open and switch 77<SP>11</SP> to close simultaneously with cam 71 causing opening of switch 75<SP>1</SP> and closing of switch 75<SP>11</SP>, so deenergizing relays Y and X, stopping the motor 31 and extinguishing amber lamp 123. Single cycles of exposure with simultaneous operation of synchronizer 102, film feed and cutting off of exposed film may then be carried out by manually closing switch 130 which energizes relay X and so lights lamp 123 and restarts motor 31, and through closed switch 75<SP>11</SP> energizes solenoid 63 so as to release the shaft 43, rotation of the shaft closing a hold on circuit for the relay X for one revolution only. Automatic severing of the film may be prevented by opening a switch 127 in the line to the solenoid 64 controlling the knife operating shaft 45. At the end of any single cycle when relay X is de-energized and X<SP>3</SP> is closed, manual operation of a switch 133 starts the motor 31 and energizes the solenoid 64 through switch 93<SP>1</SP> to cause cam 78 to operate the knife so that switch 93<SP>1</SP> opens and the solenoid 64 will be de-energized, whereby the shaft 45 will be stopped after one revolution, and also so that 93<SP>11</SP> closes, thereby maintaining the motor 31 energized until the knife has followed the cam 78 back to its normal retracted position. When only a partial frame of film remains above the gate and switch 130 is closed to make an exposure, the cycle continues until the trailing end of the film passes from beneath the roller actuating the switch 95, whereupon 95<SP>1</SP> opens and 95<SP>11</SP> closes, energizing relay Y so that the film and exposure-operating circuit operates for sixteen cycles. As the film passes from beneath the roller operating the switch 98, 9811 closes to light a red lamp 132, indicating the last exposure has been made, and 981 opens so that, at the end of the sixteen cycles and the re-opening of switch 77<SP>1</SP>, the camera stops, relay Y being de-energized.