US3601481A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Shutter release device for motion picture cameras
Assignee: Ernst Leitz Wetzlar GmbH
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Filing: 1969-12-19
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Granted: 1971-08-24
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Expires: 1989-12-19
Abstract
Abstract A shutter release device in an electrically operated motion picture camera for releasing the shutter for continuous operation or for single frame exposure. The rotating camera shutter is stopped and released by a stop member actuated by a solenoid. A bistable circuit for energizing the solenoid and the camera motor is connected in line with the camera release switch and is switched in its conductive state when the release switch is closed. Means for generating one electric pulse in dependence on every shutter rotation and for conducting the pulse to the bistable circuit are provided, which pulse causes the bistable circuit to be switched in its nonconductive state, thereby deenergizing the solenoid and the camera motor. Set means are provided at the camera which may be set either to a continuousoperation-position or to a single-frame-exposure-position. In the continuous-operation-position the set means prevent the pulse from reaching the bistable circuit while in the single-frameexposure position the pulse is conducted to the bistable circuit, switching the circuit to its nonconductive state and thereby deenergizing the solenoid and stopping the camera motor.
Inventors
- 👤 Arthur Kessler
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 00:50
CPC Classifications
G; G03; G03B; G03B21/00; G03B21/14; G03B21/32; G03B21/50
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
227 words
A shutter release device in a motion picture camera of which the rotating shutter means and the film advance means are driven by an electric motor for optionally releasing the shutter for continuous operation or for single frame exposure, the device comprising: a. a stop member (10) for stopping and releasing the rotating shutter; b. an electric camera release switch (23); c. a bistable circuit in line with said camera release switch, said circuit being switched to its conductive state when said camera release switch is closed; d. a solenoid (11) for withdrawing said stop member from said shutter and thereby releasing the latter when said solenoid is energized, said solenoid being only energized when said camera release switch is closed and said bistable circuit is in its conductive state; e. means (24, 26) for generating and conducting one electric pulse to said bistable circuit in dependence on every revolution of said shutter; and f. set means (27) for optionally setting said device to continuous operation or to single frame exposure, said set means being functionally connected to said pulse generating means so that said generated pulse switches said bistable circuit to its nonconductive state when said set means are set to single frame exposure, while said pulse is prevented from switching said circuit to its nonconductive state when said set means are set to continuous operation.
Claim 2
Dependent Claim
227 words
A shutter release device in a motion picture camera of which the rotating shutter means and the film advance means are driven by an electric motor for optionally releasing the shutter for continuous operation or for single frame exposure, the device comprising: a. a stop member (10) for stopping and releasing the rotating shutter; b. an electric camera release switch (23); c. a bistable circuit in line with said camera release switch, said circuit being switched to its conductive state when said camera release switch is closed; d. a solenoid (11) for withdrawing said stop member from said shutter and thereby releasing the latter when said solenoid is energized, said solenoid being only energized when said camera release switch is closed and said bistable circuit is in its conductive state; e. means (24, 26) for generating and conducting one electric pulse to said bistable circuit in dependence on every revolution of said shutter; and f. set means (27) for optionally setting said device to continuous operation or to single frame exposure, said set means being functionally connected to said pulse generating means so that said generated pulse switches said bistable circuit to its nonconductive state when said set means are set to single frame exposure, while said pulse is prevented from switching said circuit to its nonconductive state when said set means are set to continuous operation.
Claim 3
Dependent Claim
149 words
A shutter release device as claimed in claim 1, wherein said bistable circuit is a bistable flip-flop comprising two complementary transistors (13, 15) which are both at the same time conductive or nonconductive, and a capacitor (21) which switches said transistors to their conductive state when said camera release switch is closed, said capacitor being connected to the output side of said flip-flop for limiting the breaking voltage of said solenoid; wherein said means for generating one electric pulse in dependence on every shutter revolution is a pulse switch (24) which is closed once upon every shutter revolution and which shortens the base circuit on one of said two complementary transistors (15); and wherein said switching means for optionally setting said device to continuous operation or to single frame exposure is an electric switch (27) which in its ''''continuous operation'''' position separates said pulse switch from the power source.
Claim 4
Dependent Claim
168 words
a shutter release device as claimed in claim 1, wherein said bistable circuit comprises a locking contact (41'') in connection with said solenoid (41), a diode (42) and a capacitor (43) in parallel to said locking contact and further a first resistor (47) which permits charging of said capacitor when said locking contact is closed, and a second resistor (48) by means of which said capacitor is charged when said camera release switch (44) is opened; wherein said means for generating one electric pulse upon every shutter rotation is a closed switch (45) in line with said solenoid (41), which switch is opened upon every shutter rotation; and wherein said switch means for preventing Switching of said bistable circuit to its nonconductive state is a bridging contact (46) parallel to said closed switch (45); said contact (46) being functionally connected to said set means for setting said device to continuous operation or to single frame exposure and being closed when said set means is set to continuous operation.
Claim 5
Dependent Claim
62 words
A shutter release device as claimed in claim 1, and further comprising a timing mechanism (27) for conducting pulses at preset time intervals to the bistable circuit, said pulses being shorter that the period of one shutter revolution, thereby switching said circuit to its conductive state when said device is set to single frame exposure and said camera release means are actuated.
Claim 6
Dependent Claim
77 words
A shutter release device as claimed in claim 1, and further including a timing mechanism (57) comprising an output transistor (39, 59) of which the emitter/collector circuit is parallel to the camera release contact, the timing mechanism generating and conducting pulses at preset time intervals to the bistable circuit when the device is set to single frame exposure and said camera release means are not actuated, said pulses being longer than the period of one shutter revolution.
References Cited (Backward Citations)
US3520598A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-08-23 | 1975-02-22 | 1975-08-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-08-23 | 1979-02-22 | 1979-08-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-08-23 | 1983-02-22 | 1983-08-24 | $7700.00 | Window Closed / Lapsed |