Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
112 words
An exposure servo-control device for a camera having a shutter and an adjustable diaphragm for regulating the amount of light impinging on the film, said device comprising: an electric circuit for generating an output dependent on the deviation from an optimum aperture for an object to be photographed to the present instantaneous diaphragm aperture; an electromagnetic device including a driving coil across which said output is applied for excitation thereof, said electromagnetic device driving said diaphragm by the electromagnetic force caused by the excitation of said driving coil; switch means for short-circuiting said driving coil; and control means for intermittently actuating said switch means so that said driving coil is intermittently short-circuited.
Claim 2
Dependent Claim
112 words
An exposure servo-control device for a camera having a shutter and an adjustable diaphragm for regulating the amount of light impinging on the film, said device comprising: an electric circuit for generating an output dependent on the deviation from an optimum aperture for an object to be photographed to the present instantaneous diaphragm aperture; an electromagnetic device including a driving coil across which said output is applied for excitation thereof, said electromagnetic device driving said diaphragm by the electromagnetic force caused by the excitation of said driving coil; switch means for short-circuiting said driving coil; and control means for intermittently actuating said switch means so that said driving coil is intermittently short-circuited.
Claim 3
Dependent Claim
41 words
An exposure servo-control device as in claim 1, wherein said electric circuit includes a photoelectric element disposed to receive light from the object through the present instantaneous diaphragm aperture and circuit means responsive to said photoelectric element for generating said output.
Claim 4
Dependent Claim
29 words
An exposure servo-control device as in claim 1, wherein said control means includes a pulse generator and said switch means is responsive to the pulses from said pulse generator.
Claim 5
Dependent Claim
48 words
An exposure servo-control device as in claim 3, wherein said control means further includes a relay coil intermittently excited by the pulses from said pulse generator; and said switch means includes a mechanical switch responsive to the excitation of said relay coil for intermittently short-circuiting said driving coil.
Claim 6
Dependent Claim
34 words
An exposure servo-control device as in claim 3, wherein said switch means includes a semiconductor switching element intermittently made conductive to short-circuit said driving coil in response to the pulses from said pulse generator.
Claim 7
Dependent Claim
20 words
An exposure servo-control device as in claim 3, wherein said pulse generator generates pulses of a predetermined constant duty cycle.
Claim 8
Dependent Claim
67 words
An exposure servo-control device as defined in claim 3, wherein said control means further includes circuit means for generating a control signal dependent on the absolute value of said output and circuit means for varying the duty cycle of the pulses from said generator such that the greater the absolute value of said output, the shorter the period of time during which said drive circuit is short-circuited.
Claim 9
Dependent Claim
38 words
An exposure servo-control device as in claim 1, further comprising means for driving said camera for repeated photographing, and wherein said control means includes a member interlocked with said camera driving means for intermittently actuating said switch means.