Abstract: A developing device includes: a developer holding member that faces an image carrier on which a latent image is formed and rotating while holding developer; a developing housing with a holding member mount that mounts developer holding member, and accommodates developer; a developer container connected to the developing housing and containing developer that flows into the developing housing; a partition member disposed in the developer container and partitioning an inner space of the developer container; and a loosening member having a loosening portion disposed in the developer container and extending along one side surface and another side surface of the partition member to partition the developer container, and a drawing portion that is connected to the loosening portion and extends from a port formed in the developer container to the outside of the developer container. When the drawing portion is drawn out, the loosening portion moves to loosen the developer.

Abstract: A developing device includes: a developer holding member that faces an image carrier on which a latent image is formed and rotating while holding developer; a developing housing with a holding member mount that mounts developer holding member, and accommodates developer; a developer container connected to the developing housing and containing developer that flows into the developing housing; a partition member disposed in the developer container and partitioning an inner space of the developer container; and a loosening member having a loosening portion disposed in the developer container and extending along one side surface and another side surface of the partition member to partition the developer container, and a drawing portion that is connected to the loosening portion and extends from a port formed in the developer container to the outside of the developer container. When the drawing portion is drawn out, the loosening portion moves to loosen the developer.

Abstract: An analog-to-digital converter for a camera has a reference signal generating element, a measurement signal generating element, and pulse output means for generating pulses of pule durations corresponding respectively to signals from the generating elements. The generating elements are alternately selected to produce two pulse durations, and the ratio of these two durations is computed by pulse duration ratio computing means. Control information corresponding to the computed ratio is retrieved from memory means.

Abstract: A drive ring drivable by a stepping motor is normally urged by a spring to turn in one direction around a lens aperture. When not in use, the stepping motor is not subjected to the resilient force from the spring since the drive ring is locked against rotation by a ratchet wheel engaged by an engagement lever. The stepping motor is therefore not subjected to undue stresses and is prevented from malfunctioning. Consequently, focusing failures and exposure adjustment failures which could otherwise arise from malfunctioning of the stepping motor are prevented from occurring. In operation, a solenoid is energized to move the engagement lever out of engagement with the ratchet wheel, which is then freed to allow the drive ring to be turned by the stepping motor.

Abstract: A camera shutter has an automatic focusing lens operative when actuated to effect an automatic focusing operation. An actuating ring is normally placed in a non-operating region and momentarily shifted to an operating region during the automatic focusing operation. The actuating ring is sequentially displaceable in forward and reverse direction through the operating region to actuate the automatic focusing lens, and displaceable in the forward and reverse directions in the non-operating region without effecting actuation of the automatic focusing lens. A ratchet mechanism is coupled to the actuating ring for selectively locking and unlocking the actuating ring in the non-operating region in response to the displacement thereof in the forward and reverse directions. A bi-directionally rotatable stepping motor is connected to drive the actuating ring to displace the same in the forward and reverse directions.

Abstract: A program shutter has a plurality of shutter sectors driven in opening and closing directions by a reversible stepping motor to define a lens aperture during an exposure operation. An arithmetic circuit calculates an exposure amount corresponding to the brightness of the object being photographed, and a counting circuit outputs a pulse count corresponding to the number of steps through which the stepping motor should be rotated based on the calculated exposure amount. A pulse circuit produces driving pulses equal in number to the number of steps determined by the counting circuit, and a time circuit determines the ON/OFF periods of the driving pulses based on the calculated exposure amount. The driving pulses are applied to the stepping motor through a driving circuit to accordingly drive the shutter sectors in the opening and closing directions during the exposure operation.

Abstract: A power circuit for a camera comprising a power activation means containing a release switch for activating the camera, a step-up means for starting to step up the voltage of a battery by the power activation means, a CPU which is driven by an output of the step-up means so as to control the operation of the camera and which has a reset terminal for stopping the operation, and a voltage detecting means for detecting the output voltage of the step-up means and for generating a detection signal when the voltage is lower than a set value which has previously been determined, the set value being set to correspond to the limiting operation voltage of the CPU and, when the output voltage of the step-up means is lower than the limiting operation voltage of the CPU, the CPU being reset and stopped to operate.

Abstract: A camera shutter digital control circuit having a counter for counting a number of pulses representative of exposure time and for reading-out the counted pulses to control exposure time. An adjustable delay circuit synchronizes shutter opening and the initiation of memory read-out. Upon the initiation of shutter opening a signal is applied to the delay circuit, which is adjusted to develop a delay equal to a particular shutter opening time. The delayed signal is then applied to initiate reading-out of the control pulses so that the exposure time is controlled in synchronism with the shutter opening.

Abstract: An electric shutter circuit having an exposure time display disabled in synchronism with the opening of a camera shutter. A brightness-time conversion circuit and a pulse generator together develops a plurality of pulses the number of which is representative of the exposure time and which are stored in a reversible counter. Upon actuation of a shutter release mechanism a display circuit is enabled to display the exposure time by displaying a visual signal determined by the number of pulses stored in the reversible counter. The display circuit is disabled in synchronism with the shutter opening. In one embodiment a Schmidt trigger circuit is triggered by the shutter release mechanism to disable the display circuit.

Abstract: An exposure time control device of an electric camera shutter includes a brightness time conversion circuit for developing a single pulse having a width representative of the brightness of a subject to be photographed and a reference pulse generating circuit for generating reference pulses at a standard rate. A reversible counter counts the reference pulses for a period of time equal to the duration of the single pulse. Upon termination of the single pulse, a reversible counter control circuit applies control signals to the reversible counter to read-out the count stored therein for controlling the shutter exposure time. A selector switch selects the input position of the reference pulses to the reversible counter in dependence upon exposure time factors other than brightness of the subject thereby enabling the selection of the exposure time in accordance with the subject brightness as well as other factors, such as film sensitivity and diaphragm setting.

Abstract: An exposure time control device of an electric shutter includes a brightness-time conversion circuit for developing a single pulse having a width representative of the brightness of a scene to be photographed and a standard pulse generating circuit for generating pulses at a standard rate. A reversible counter counts the standard pulses for a period of time equal to the duration of the single pulse. Upon termination of the single pulse, a reversible counter control circuit applies control signals to the reversible counter to read-out the count stored therein for controlling the shutter exposure time. A delay circuit develops a trigger pulse upon opening of the shutter. The trigger pulse is applied to the reversible counter control circuit, and if it is applied prior to the termination of the single pulse, read-out of the count stored in the reversible counter is initiated prior to termination of the single pulse.

Abstract: An electric camera shutter of the type having a digital recording and reproducing system has a self-timer mode and has a counter circuit for counting and memorizing pulses produced by a pulse generator. In one mode of operation, the exposure time is controlled in accordance with the memorized content of the counter circuit and when in the self-timer mode, the output of the counter circuit controls the energization of a self-timer operation indicator circuit which indicates operation in the self-timer mode.

Abstract: A shutter control circuit including a brightness-time conversion circuit for developing an output pulse having a duration representative of exposure time, and a standard pulse generating circuit for generating standard pulses at a certain rate. A reversible counter operable in an addition mode and a subtraction mode counts the standard pulses for the duration of the output pulse of the brightness-time conversion circuit so that the number of counted pulses is representative of exposure time. The reversible counter is then operated in a subtraction mode to read-out the counted pulses to control exposure time. The shutter control circuit further includes circuitry for operating the counter in the addition mode and for applying a selectable number of standard pulses to the reversible counter in order to determine exposure time.

Abstract: A digital exposure time control circuit including a standard pulse generating circuit for developing standard rate pulses which are applied under control of a brightness-time conversion circuit to a dividing circuit, and subsequently counted in a reversible counter operating in a counting mode. The number of standard pulses counted are controlled by the brightness-time conversion circuit to be proportional to an exposure time, and the counted pulses are subsequently read-out from the counter to control exposure time. The exposure time control circuit also includes a self-timer control circuit which is responsive to a predetermined number of counted pulses to clear the reversible counter, and enable the brightness-time conversion circuit when the number of counted pulses exceeds the predetermined number in order to develop a delay time, determined by the predetermined number of pulses to which the self-timer is responsive, before the start of counting the pulses for controlling exposure time.

Abstract: An electronic camera shutter control circuit having a reversible counter for counting a number of pulses proportional to the duration of an exposure time. When the camera shutter is opened pulses are subtracted from the memory content of the reversible counter until the counter content is zero and the exposure is terminated. The reversible counter includes a final stage which does not change state if the number of pulses applied to the counter exceeds the memory capacity of the counter. For this condition the exposure time is first controlled by the charging time of a capacitor until a voltage stored in the capacitor exceeds a certain value whereupon the memory content of the counter is subtracted until it is zero and the exposure is terminated.